
Obviously it's different for everyone, and you'd probably do best straight up asking him what would help. But personally i find it helpful when my bf is a) vocal about liking that part of me or finding it attractive and b) not pushy about doing anything that makes me uncomfortable, even if it's something that could be assumed would be affirming
I was with someone in the past who repeatedly asked to give me head and tried to reassure me it was "the same as a cis guy's dick to her" despite me telling her no and that i was uncomfortable with the idea every time; she was trying to be helpful because in her mind it sounded affirming, but the excessive pushing just made me even more uncomfortable and dysphoric about it