First tell me, what is your interest. Which thing you want to sell. Make it your passion and you will be a successful. If you want to sell cars, then know about cars, read about cars and then write about cars. If you want to see Laptops then repeat all the above steps.
Search for an offer/product that you have most experience with. Then write a review/promote it using SEO/PPC.
you can promote your affiliate links in any manner like in signature for many forums..............if they don't have such rules to include affliate links in forum sign.......................and other on article ....................blog commentings..........
If you want to promote your business and look for potential clients to affiliate try promoting it on social networking sites like eZdia , facebook etc. I prefer ezdia as its has many features which will bring you clients as well as people offering solutions for your business problems.
Before you start thinking about your methods, take a step back and work out what is going to pay you the most return for your efforts: What market niche do you stand a chance of competing in? Which products pay the highest commissions? What do people tend to buy over the net? So it may be worth entering a competitive niche if the payouts are high and you don't need many sales, or a non-competitive niche, low payouts - but high volume of sales - weigh it all up. Which programs offer the most generous compensation? For example, from memory Amazon's program only offer a 24hr cookie (so if you refer a visitor who doesn't buy then, but a day later, you receive $0), and does not pay for return purchases. (Correct me if things have changed!?) Then start to learn about creating web pages on your chosen field(s). There are lots of helpful affiliate programs out there who help you with that, they want your traffic.