I'm responding as a long time VA who has seen the benefits that clients have experienced because of my own services, or that of my team members.

The important thing is to have some idea of what you need to have done and what you can confidently delegate to someone else. The biggest time waster for you and your VA is when you don't know what you want done. And this does happen a lot. Clients know they need help but often can't determine what to give over first.

Doing your own personal time and motion study can often help - documenting what you do each day for a week and asssessing what is important and needs to be done but isn't earning you direct income. It's these things that you can engage a VA for because, while they're working on those things, you can be doing things that are income producing.