How Do I Explore My Bisexuality in a Monogamous Relationship?

Dear Betty,
I'm 20 years old and have been with my current partner for 3 years. He is strictly monogamous and I think " I'm recently coming into my identity as bisexual as well and have been really wishing I could it explore it more. It's not that I don't love my partner and cherish the way our relationship is, it's just that I wish I could explore other relationships as well.
Do you have any advice?
Dear M,