There are two main ways of bonding rabbits, side by side or the 24/7 method.
Side by side
Set up two areas, side by side where the rabbits can sniff each other without biting/harming each other.
RWAF advice:
24/7 method
Another option is the 24/7 method, this consists of placing the rabbits together in small, neutral area. It is essential that the rabbits are fullly supervised for the first 24 hours. Although intense, this method is often quicker and it is clear early on whether the rabbits are compatible or not.
This website is helpful, see Technique 2 for more guidance
These websites also offer some excellent advice.
rabbitwelfare.co.uk/pairing-up-rabbits-bonding
BONDING&BEHAVIOUR – Baby Blue Bee Bunnies
https://cottontails-rescue.org.uk/information/bonding-bunnies/