I guess everyone wants to design pixel perfect layouts, but sometimes we don’t get the crisp looking elements we want, instead we get elements that appear to be kind of smooth and messy. Most of us have experienced the one extra pixel horror or pixel difference.
So what is the magic that avoids those bad situations - snap! It’s called snap to pixels, there is also snap to grid so you should just snap to everything you can until you get the pixel perfection. Here is an example of what it does:
To activate snap to pixels you need to select the Shape tool from the tools palette. On the top menu bar you will see bunch of shapes. Select the rectangle or rounded rectangle shape, click the drop-down arrow on the right of the shape options. It will open a panel, on the bottom-right just check the box “Snap to pixels”.