1. Take your time to find and work with an adviser but not too long: It should take a bit of research and a preliminary meeting or two to find the right planner for you. Do the work but don't delay unnecessarily.
2. Focus on goals not just returns. A good planner needs to assess where you are at, financially and at life stage, and where you want to be. They do not usually pick winning stocks anymore than winning horses.
3. Don't be shy. A planner you stick with is likely to get to know you and your significant others, and your relationships with and about money very well. You may tell them things you wouldn't say to others.
4. Ask questions. At all stages of the business relationship don't be afraid to ask powerful questions - most of all if you don't understand something. A good planner wants you to know what's going on and why and they should welcome a good question or two. Also listen to the answers!
5. Get a little more educated and empowered about the world of money. It's not as complicated as many tend to believe. I've just read a great book, which demystifies and demythologises our feelings about finance, called How to Speak Money by John Lanchester. There are other titles which will make you feel more confident and be more interesting when talking to your adviser.