How to tell if my husband is cheatig on me because he keeps accusing me and I'm not cheating

Catch him in bed with someone, why do you think he is cheating. Have you sat down and talked why he things you are cheating ?

Well, what does your gut tell you?
Usually woman just know, their behavior changes in one way or another, I would track his cell phone calls to see whom he is speaking with and how often. Also, you should pay attention to any changes in your sex life with him, that's a big give away!
Catching him in bed with another woman is unrealistic and immature.
My guess is if u are suspecting it then he probably is.