The best recommendations I know are 1. using a bunny burrito, where you wrap a bunny in a towel with only their head sticking out, then gently pull out one paw at a time (sometimes you need to rewrap for access) and trim the nails. Best done by 2 people. 2. Sit on the floor and set your bunny between your legs facing away from you, gently holding him in place between your thighs. You can use a treat or lettuce for munching while you then press down firmly but gently on his shoulders with one hand, (dominance move) then take a paw and cut nails while he’s between your legs holding still.
My frequent and best recommendation is the PRESS/PRESS/CLIP technique. Once you have the paw in hand, set the scissors against the nail, and press it, but do NOT clip the first time. Continue to hold, press again, then on the third press clip it through. If you have gone too low on the nail, you will touch the quik, a vein that will bleed and hurt. If you touch the quik on the first press, your bunny will jerk his paw away hard. This will help you find a new spot that closer to the tip and not hit the quik again. It’s especially helpful for dark nailed bunnies where you can’t see the color change that indicates the place of the quik. Do this with every toe until finished. If you manage to trim without ever cutting the quik, causing bleeding and pain, your bunny will be more cooperative the next time.
And have a small dish of plain corn starch (the stuff in your baking supplies) in case he does bleed. Apply it to a bleeding toe to absorb and stop it. A styptic pen is also used (my vet did). corn starch is also safe when bunny licks his wound.