how do you ride dick

I've never rode my boyfriend bc I have no idea how; we lost it to eachother we've been together for 4 years and we started having sex about 6 months ago and I have NEVER been on top. I feel bad because he always asks but I'm scared to mess it up. Please explain to me how to do it 😂 we were supposed to wait till mirage together by the night he proposed we couldn't help ourselves and we figured we will be married within the year anyway so we did it.