Before you begin, check with a building inspector about local code requirements.
Prior to installing the stone, map out a design on the ground. Be sure to choose veneer from different boxes to vary the shapes and colors.
Install the corner pieces first, then work your way down from the top. This will prevent mortar from staining the stones below.
If you discover a mortar drip on one of the stones, wait for it to dry before brushing it off with a whisk broom. Smears can permanently stain the stone.
When possible, hide edges that you trimmed by pointing them up or down, above or below eye level.