Help with prep

I am currently 20+5 and due on the 30th of june. I am thinking of an april baby shower as my mum is getting married in may and i would like the baby shower before her wedding so she doesnt have to think about my baby shower afterwards and can enjoy being married during the school holidays (shes a school teacher). The men will be invited and it is being held at my MILs. I have no idea where to start. I already have my list of who is invited but i have no idea what to do next. Anyone help?