how can I enjoy giving head?

Goodness I don't love giving my bf head at all. His cum taste horrible but I haven't ever told him that. I feel like he knows it does though bc one time he asked me "well you're a pro at swallowing aren't you?" And I just kinda giggled, but it tastes horrible and makes me want to gag every time. I would never ever ever tell him this. What should I do to enjoy pleasing him this way more?