Making A MNS

Do you need Google Adwords to rank high in Google? Or is backlinking and social media enough?

I've also read on this forum, if an affiliate link is present in your website you won't rank high in Google. Is this true? And would cloaking a link solve this problem?

Google Adwords doesn't make you rank in SERPs - you can pay for advertisement through it, and will have to pay for every click.

If you find some good keywords you will be able to rank your website with the help of good backlinks. Make some keywords research, write a bunch of articles with these keywords, and then start working on backlinks and social media. Forum signatures can be a good way to get your niche site off the ground - it will help you rank, and at the same time generate good targeted traffic from day 1.

If you are building a mns its all about keyword research....know exactly what the target is and aim everything towards it.....you dont need adwords to rank........links are always good a well seo'd site with fresh content is better. ...google dont care about you promoting an affiliate.....no point doing affiliates until you have some traffic......dont mess with cloaking unless you really know what you are doing.

So my main source of income from a MNS should always be Google Adsense?

Not always, you could also use Amazon affiliates and many other similar programs, depending on your keyword.

Adsense and Ranking the the SERPs are two different things.
However, using both methods is definitely a great idea. Each has its own advantages.