Photoshop: Using the Elliptical Marquee Tool - Make Simple Curves

Step 3 - Adding Button Elements - Making Simple Curves Using Circles. Making sure you are working with the new layer you created called Left Curve, it's now time to start adding button elements to your blank canvas (there will be 3 pieces to your button and we are creating the first piece right now). The left part of the website button you are going to create is actually a circle which will become the left-side curve of your website button. One simple way to create a curve is to use the Elliptical Marquee which is located in the Tools Palette. As the example below illustrates, simply click and hold down your left mouse button where you see the rectangular icon. From there a list of options should appear and include "Elliptical MARQUEE TOOL". Go ahead and select it.

Step 3 - Choosing Elliptical Marquee Tool for Simple Curves

Step 4 - Using the Elliptical Marquee tool go ahead and draw a small circle in the left portion of your canvas.
The circle you would see might look like this -->While drawing a circle if you hold down the SHIFT KEY you can make a perfect circle. For the example I used a perfect circle to define my button's left curve but later you may decide an oval shape can work as well and creates a subtle difference in the way your final web button will look.

Step 5 - Coloring your circle. <-- right now your circle needs to be filled with some color. Go to the Tools Palette and Choose "Set Foreground Color" by clicking on it (the top swatch of color).
Choose gray #CCCCCC from your color choices (recommended for this tutorial) but any color will probably work. We will later apply a gradient overlay and color from Photoshop's layer styles so don't worry too much about color at this stage.

Step 5 - Filling Your Circle with a Color Using the Paint Bucket