Tip: If you want to change the measurements, simply press Ctrl/Cmd+R to enable the Rulers then right-click on the ruler and select the measurement you’d like to use.

Smart Guides also let you create matched spacing so that you can duplicate a layer to another position and repeat this with the same spacing you had before. For example, let’s say we want to duplicate this circle three times. Simply hold the Alt or Option key then drag it towards the right.

Repeat the same thing by holding Alt or Option and dragging another circle towards the right. Photoshop will automatically snap this circle so that the spacing matches.