I started with something that I knew a lot about, was interested in finding out more information, and something I was actively participating in. That really helps out a lot. So if young affiliate is/was a poker player or a casino player or bingo player that is where I would start.
For a new affiliate, there is a lot to learn on the technical side of things (hosting, design, SEO, affiliate tags, redirects) that make it tough enough even if you are an expert on the subject. If you know nothing about being an affiliate or on the subject matter it is going to be difficult to get going and keep going.
I was very active as an online casino player, so I had a lot of experience to share and a lot of answers to questions that people were asking. It was easy to provide useful information as I had been there before and had run into the same questions and problems.
Participating (or lurking) and reading sticky posts and FAQ’s in active player forums is great for figuring out what kind of information players are looking for. I saw the same kind of questions over and over and was often answering them in the forum myself. It wasn’t very difficult to go from answering questions on a forum to having pages on a website dedicated to the questions being asked with detailed answers.
For the first site, I would try to go very tightly niche. Targeting a specific casino, poker room, game, something specific is much easier niche to gain any traction in then targeting “Poker” or “Casino” or “Bingo”. for example, focusing on “doylesroom poker bonus codes” or similar. I have seen so many people quit before their site had a chance because they went super broad and were not ranking or could not see any progress.