For some people, tutorials seem like a waste of time. I have a lengthy and meandering argument of qualified disagreement somewhere in my head on that score that will probably make it out one of these days, but in the mean time, in sympathy for the anti-tutorial cause, I'm creating this page.
This is intended to act as guidance for the tutorial-adverse. Turns out Photoshop has a some really -- brace yourselves for this, it's not true of a lot of programs -- helpful help files. Of course if you don't know what functions are called, or which you should be learning about in what order, it can seem a bit overwhelming. Here's were this page comes in... I'm going to try to outline a course of study that would have worked for me, geared towards the creation of fanart (since most books you'll find in stores aren't!). The order is a mostly but not entirely arbitrary, so try it if it's not too much structure for you; otherwise, just dive in at will. But if I was gonna teach a course in Photoshop, this is the syllabus I'd use, and the order I'd do it in.
Use the help files to find the tool I'm talking about, and then play around with it till you understand how it works. Think of it as a self-guided tutorial. I'll start by assuming you're a rank amateur. If you're not, just skip over the parts you've already played with... incidentally, most of this will work with other graphics programs too, there might just be some different terminology. I'm working with PS5, so if you're on version 6, 7, CS etc, there might be some slight shifts in terminology, but you should still be able to find things in the help files by typing in words from my descriptions.
Note also that it's helpful to have some pictures downloaded or scanned to start with. Open one or more up and start playing...
Learn how to: apply a filter to a layer. Change filter settings. Fade a filter. Change the blend on a filter. Get real familiar with the most useful filters: the various Blur:Gaussian Blur and Blur:Motion Blur; Noise: Median; Sharpen: Unsharp mask.
Learn how to: Use all the tools under the Image->Adjust menu (start with: levels, color balance, hue/saturation, selective color). Then go back and look at the ones that allow you to affect individual channels (levels, curves, hue/saturation) and play with tweaking them instead of the RGB composite
Learn how to: change image size (pixel dimensions) to downsample (shrink) an image. Increase the work canvas size. Understand image resolution (key point: you can always make images smaller and retain quality. You make them bigger, they lose quality, even though they gain file size). Decide how big you should be working (ie, for digital images that won't ever be printed, wider than 1600 pixels is probably pointless. Max dimensions of between 800-1600 are typical of fanart).
Learn how to: crop (remove the unwanted edges) an image down to a smaller size using the crop tool. Understand the difference between cropping to a certain size (crop-and-downsize at the same time) and just plain cropping.
Learn how to: Add text using the type tool, change font, change size, change color. Edit existing text. Use Transform to resize text on the canvas, or to rotate it to a different angle. Use Layer Effects to add drop-shadows, beveling, etc. Use the move tool to position text. Use the alt-enter & control-enter to change the color of text. Render a text layer (transform it into a picture of text instead of editable text).
Learn how to: zoom in and out on your image (shortcut: control-- (minus sign) and control-+ (plus sign)). Use the hand tool on a zoomed image to move around (shortcut: space bar) Resize the working window. Temporarily hide the tools with tab key. Notice how 100% is the view that gives you a true idea of what your image looks like. Shrunk down can produce moires and other strange effects (invisible 1-pixel wide lines, for example))
Learn how to: save a flattened JPEG copy. Save a PSD file. Switch from RGB mode to Index mode to save a GIF copy. Save a gif with certain colors made transparent. Save an in progress back-up copy with the "save-as unflattened PSD" command.
Use the rectangular and circular marquee tool to make a selection. Use the lasso tools to make a selection. Use the magic wand to make a selection. Use the color range tool (under the "select" menu) to make a selection. Feather a selection. Invert a selection. Grow/Shrink a selection. Smooth a selection. use the "similar" selection to add to a selection. Use the "alt" key with the selection tools to subtract from an existing selection. Use Quick Mask ("Q" key) and painting tools to modify a selection. Transform a selection. Save a selection. Load a saved selection.
Learn how to: cut a selection and move to another location. create a duplicate of a selection by holding down the alt key as you move. copy a selection to the clip board and paste (forms a new layer, see below)
Learn how to: copy-paste from selections in different files to a single file to create layers. Use the eraser to remove parts of layers. Change the layer blend modes. Change the layer opacity (transparency). Rearrange the order of layers in the layers palette. Move objects in layers on the canvas using the move tool. Duplicate layers. Delete layers. Add new blank layers. Snap objects on layers to guide lines. Link layers together so that you can move them in tandem. Use the align/distribute commands to fix the spacing on objects on different (linked) layers. Select an object on a layer by double-clicking the layer in the layers palette.
Learn how to: apply a layer affect to a text or regular layer. Clear/copy/paste layer effects. Edit a preexisting layer effect. Render a layer effect to its own layer.
Learn how to: paint (hold the mouse button down and move) or stamp (move the cursor to a location, stop, and click the mouse button once) with the airbrush, brush, pencil tool. Select a different brush. Make a line with the line tool. Use the paint bucket to fill an area. Use the edit->fill command to fill an area. Define a pattern, and fill an area with that pattern. Apply a gradient. Load a custom brush set made by someone else. Define your own brush and use it with the airbrush or brush tool. Stroke a selection. Change the foreground and background colors on the floating toolbar. Use the stamp tool to clone an area.
See also my tutorial on brushes
Learn how to: shrink or increase the size of an object on a layer. Rotate an object. Distort/Skew/Perspective transform an object.
Add a layer mask to an existing layer. Paint on a mask with brush/airbrush/stamp. Use filters and color adjustments on a mask. Use copy/paste/move/duplicate tools on a mask. Add layer effects to a layer with a mask.
See also my tutorial on the subject
Add an adjustment layer. Paint on the adjustment layer to mask its effects on underlying layers. Edit an adjustment after it's been made.
See also my tutorial on the subject
Clip or group layers together. Move clipped layers independently or together (by linking them). Clip texture layers to text layers.
See also my tutorial on the subject
Use the pen tool to create paths. Use the "convert selection to path" tool. Convert the path to a selection and/or use the stroke/fill path commands.
Add lighting effects using Render->Lighting Effects. Create 3-d Effects by applying the lighting effect to an alpha channel.
Learn short cuts for all the main tools and other functions you use a lot. Learn a few at a time. trust me, there's a reason they call 'em shortcuts... get even a few down (D,X,space bar,alt,B,J,[,] are some of my most frequently used) and you'll be able to spend more time thinking about what you want to do and trying things out and less time actually executing things.
Record your own actions to speed up tasks you do frequently. Assign actions to keyboard shortcuts for maximum efficiency. Apply actions to an entire folder of images via batch processing.
Now that you're up on the tools, here are a few directions to experiment in. Of course, you should definitely try to come up with your own, this is just to get your started...
There are of course a zillion other things to try. Basically, just keep trying different things in different combinations, and you're bound to stumble across a cool effect sooner or later. Then the trick is to remember how you did it!