Let's assume you've already done two things:

1. Produced killer Eversink creative directed at the consumers likely in the market for putters.
2. Decided to serve it on the (fictional) Gazillion advertising network, with access to hundreds of sites at once rather than on a single site.

Next, you choose BT segments from those Gazillion offers. This time it's a no-brainer because Gazillion has a "Golf Nuts" category especially for golfers. You select that category, and also specify that to get into the frame users must do the things that qualify them as Golf Nuts at least four times in two weeks.

You don't want to waste ammo on chance visitors

Next: Let technology do its stuff