Some tips I picked up along the way.
Use spacers (or story rods)
Ditch the ruler whenever possible as there is no way you can measure the exact same height twice (really). Ideal for drawer slides, ...
Predrill before screwing
Always thought this was a wast of time, until I had a nice walnut piece split on me.
Leave pieces long
Cut them to length as a final step.
Drill a screw close to the border
Leave piece long, screw, then saw off next to screw
Don't skip grits when sanding
Design/build for the tools you have (access to)