Think like a dating site and consider how they make money...
- Language of members: If the dating site only supports English speaking members, don't send French (for example) traffic.
- Country of origin: Similar to the above point, but you should focus on the tier 1 countries that have the lowest % of fraud... USA, Canada, UK are generally the best unless the dating site is European and members speaking a different language other than English.
- Gender: In most cases, dating sites are only interested in Men. Don't refer females users if you expect to get paid.
- Quality of lead - in this case, think like a dating customer. Who are the people using the internet for adult dating and where do they surf? You can send all the traffic you want, but if they aren't interested in joining a dating site, they won't convert. period.
If you follow these simple guidelines, you will be off to a good start. Everything else you do is secondary.
Hope this helps. Good luck!