It is possible to list 5 or 25 points for creating an affiliate site but the best answer probably is just a single point as the critical key point. Make sure your website has value and a good Unique Selling Point (USP). Just ask yourself what makes your website so special in comparison to the others. Does it offer a unique value or service that your competitors don't have. In 2013 it is now tougher to make good quality sites done with less effort. Most new sites usually seem like a copy of another site. If your content and value doesn't stand out then you can expect it to be challenging to get search traffic or to compete for referrals. When your site offers good value to your users, they will naturally want to share it with others. When you make a quality website you prevent your users from leaving your site and going to another one and they will stay loyal to you.
In theory revenue share can earn an affiliate/webmaster more money as some referred players can play for years earning you commissions. CPA are better for short term payments up front regardless of the player value. The advantage of CPA as a choice for affiliate commissions is that affiliates get their payments regardless of changes in an affiliate program or when gambling regulations can close off markets. With many major affiliate programs retroactively changing their terms and conditions, this has cut off lifetime commissions on some affiliates. If you don't trust to have a long term partnership with an affiliate program or you are not sure if you will be a gambling affiliate full time then you might want to consider CPA over revenue share. Another reason is if an affiliate program has unfavourable terms and conditions, you will want to work with these programs on a CPA basis to prevent problems.