Step 1:

Start a new document of size 250×250.
We can create our shapes using the following tools

Step 2:
Let’s draw some shape using the rectangle marquee tool

Use the Pain Bucket tool and fill some colour into the box

Step 3:

Let’s draw some shape using the eleptical marquee tool

Use the Pain Bucket tool and fill some colour into the circle

Step 4:

Let’s use both rectangle and eleptical marquee tool to create other shapes

This is a bit tricky

draw a rectangle first and hold alt and draw circle over it using the eleptical tool and fill it with the paint tool
I got this

if u see clearly u can see the circle that i drew. I did it so that u get a clear picture.
so that’s the trick holding alt to remove the part u don’t want and u can hold shift to add the circle to the rectangle.

let me show u what i got by holding shift when drawing a new circle over the rectangle.

that’s all now it’s on keep playing with various shapes.

here are some more examples

Step 1:
Select File > New and select a new canvas of width 150 px and height 100 px and press ok.

Step 2:
Now create a new layer and Select the Rounded rectangle tool to create a shape like this. Then on the layer floating menu press ctrl+click to make the selection. Then create a new layer and delete the previous layer(shape layer). Now fill up the selection with red colour.

Step 3:
Now with the selection still on go to Layer > Layer Style > Bevel and Emboss and select style as Inner Bevel technique as Smooth and Depth as shown here.Now the button looks like this. As you can see some 3d effect now. Now we need to improve the effect so that it looks more 3D.


Step 4:
Let’s add some shadow to the button to give it some depth. To apply shadow go to Layer > Layer Style > Drop Shadow.. . Here make the following setting as shown in the image. Now you can see that our button has got more depth.


Step 5:

Now Let’s add some Inner shadow. Use the following settings as shown in the figure. Now with this step we are finished. Our button looks cool now .