Do you mean regular contests like CQ WW and the ARRL DX test? For those ya just get stuck in and work what you can. Make it as fun or as serious as you like. It's a great way to test a new antenna because there will be a lot of activity, just don't expect any meaningful signal reports and don't expect anyone to hang around for a chat. But at least you can get a feel for the sort of ability to communicate you can achieve with a given antenna.