How do you kiss someone with a really big mouth?

He has really big, really soft lips and when I kiss him I feel like he swallows my mouth. He’s not a bad kisser it’s just, my mouth is so small compared to his and I’m not used to it at all and I literally don’t understand how to kiss him?

Maybe I’m stupid but I was with only one man for so long and now I’m with someone new who has plump lips and I’m like how do