Use Easy Values

A thing I try to keep in mind is to use values that are easy to calculate, like 10, 100,... Take for example the creation of a dotted pattern or concentric circles. You could use 200 px for the width and height of the smallest circle, the next one 250 px, then 300 px, 350 px and so on... It makes things much easy to work with. When you use values like this, it's also easy to line things up perfectly via X and Y coordination values in the Control bar at the top. Then when you have Smart Guides, and make sure you have Snap to Point enabled (instead of Snap to Pixel) you can position your elements even faster.

