M.T.
Hi A.,
When a baby is latched well and eating actively, they can't bite - it's like a vacuum seal. You can't teach a six month old not to bite. However, biting normally happens toward the end of the feeding, when baby isn't actively, continually eating anymore but is more playing at the breast, suck, sip, rest, rest, suck, rest, sip, rest, rest. When you see that he's not actively eating anymore, take him off the breast, end the feeding when he gets to that playing at the breast, last few lazy sips, extending the feeding stage.
Good luck