How to not cry when talking to boyfriend?

I have to talk to my boyfriend tonight about some stuff that's been bothering me about out relationship. every time I try, I cry and I can never get to what Im trying to say and nothing ever gets resolved. Do you have any like tricks or anything on how to not cry in a situation like that? I know it sounds ind of dumb, but i've had to put away these feelings ive been having for some time now because I always end up crying and forget everything im trying to say and nothing get solved. I just want to be strong and resolve our problems.