Flat Bench

How to adjust

There is no backrest angle to adjust (the key difference from the adjustable bench) — the only choice is where you position yourself along its length.

Lie or sit on the bench for your dumbbell/barbell exercise, keeping feet flat on the floor for stability.
Perform your press, row, or other exercise.
Dismount by rolling to one side rather than sitting straight up with weight in hand.

Never attempt a heavy barbell bench press on a plain flat bench without a rack or a spotter, since there's no safety catch if you fail a rep.
If you fail a rep with dumbbells, pull them into your chest, roll to one side and set them on the floor before sitting up; when you train alone, don't grind out that last rep.
Keep your feet planted for stability throughout any pressing movement.
Set weights down safely before changing position, don't twist while still loaded.