Well, for me it used to be pretty simple: you fall into bed with them a few hours after meeting them and then have an ongoing relationship that lasts for about 2 years, at which point they break your heart (usually by falling in love with someone else the slow way and falling out of love with you - the poly one did an interesting (!) variant on this theme which would take too long to discuss here). I really don't recommend this route, because the heartbreak at the end sucks badly. Hense I'm trying another more complex way of doing things that involves being cautious as all hell. The main reason it's working is because I tend to be more passive in terms of initiating things, so I feel really ackward about being active. I'm still not sure if it's the best path, but it does seem to be going OK.