How can I make it tighter?!

So sex is very good with my boyfriend but we already have four years together and I honestly feel like I don't satisfy him enough. He tells me I'm the best and he loves the sex but I feel like I'm too loose ( am I crazy for thinking that) does anyone have any tips on how to spice things up or how to tighten my "who ha" 
I'll try out all the things and positions I really want to restore the passion between my fiancé and I