I've have a gaming website with a lot of tutorials and guides. Around 20000 page views/day. At the moment I'm trying to create a premium section with exclusive guides.
What other ways can I use to monetize it? I've thought about using mobile installs but I don't know any network that has a lot of gaming mobile offers.
Clickbank offers. Depending on what games you're focusing on, there may well be Clickbank offers for the game that you target. For obvious reasons, they'll tend to convert pretty well.
Set up Revived Adserver, use a mixture of the provided banners ( unlike most verticals, Clickbank affiliate banners are often pretty good) and your own, and you should be able to achieve a decent ROI.
Adsense can do pretty well too on games sites, believe it or not - have you tried it?
Finally, if you can get an email list going, do so! That's probably the best way to get higher ROI out of a community like this long-term.
The game is very popular among teenagers so I don't think they have a credit card. I was thinking about an offer wall with app installs in order to get access to the premium section.