1. Create a new document 500 x 500 pixels with a white background. Make sure that the colour mode is RGB colour.
2. Turn on the grid. To do this go to View - Show - Grid (or press ctrl+shift+2 on PC, apple key+shift+2 on Mac).
3. Select the elliptical marquee tool - that’s the circular dotted selection tool thingy in plain English. If you can’t see it, it’s hidden underneath the rectangular marquee tool (the rectangular dotted selection tool thingy) 
. To access it, click and hold on the rectangular marquee tool, this opens up a submenu, then click on the elliptical tool 
.
4. Move the cross-hair over a junction of a main horizontal and vertical grid line near to the top right hand corner of the grid. Press and hold down the shift button to make sure you create a perfectly circular selection, then, at the same time, click and hold the left mouse button and drag the cursor away from the corner. Keep dragging until you have a nice circular marquee (selection) in the middle.
5. Select the gradient tool. If you can’t see it, it’ll be hidden under the paint bucket 
. Click and hold on the paint bucket and then click on the gradient tool 
.
6. On the options bar (the bar across the top of the workspace, which holds the various options for whatever tool you’re using, hence Options Bar - good name eh?), click on the downward pointing arrow on the right hand side of the oblong sample box (see below).
If the default gradients aren’t visible, click on the right pointing arrow on the right hand side of the gradients and select Reset Gradients, and click OK.
7. Select the spectrum gradient 
by double-clicking on it.
8. From the five gradient types, select the Angle Gradient (see above). Click in the Reverse box to reverse the gradient.
9. Move the cross-hair to the exact centre of the circular marquee. Press and hold down the shift key (this locks the cursor so you can only move it vertically or horizontally - a really handy tip for drawing straight lines if you’ve had three vodkas too many!) and at the same time drag the cursor up beyond the edge of the marquee. Now let go.
10. TA DA!!
You’ve created a Photoshop Colour Wheel. Press Ctrl+D (apple key+D Mac) to remove the marquee. Press Ctrl+Shift+2 (apple key+Shift+2 Mac) to remove the grid. This should be the result...
