What can i do to help stand up for myself?

Im a very timid person and im in my 30s..i hate to say bit alot of stuff i just take. I feel so much anxiety but i dont want to.be this way forever. What exercises can i take to help stand up for myself? @ASW- My therapist isnt really helping. Shes a good listener but not really giving me hwk to do. This is the 3rd therapist thats been unhelpful.@K-Okay, ill try that.