The best online marketing that you can do is the one that suits you. There our many different ways to market online and it's best to do as many as possible but some of them you just won't get along with, which is fine.
When people are marketing online they are normally selling something and wanting people to pay money. But when you are advertising your link you should let people know you are not selling anythingand that it will cost them nothing. This is because most of the time people aren't looking to buy anything. Next you should explain in detail what the system is and how it works. It's best to leave out bad points as it will put people off. Some people will advertise well but let themself down by not offering a way for there referrals to contact them. Your referrals like to know they have help if they need it (this is why i always have my E-mail address on my pages).
I'll write a couple ways that i'm familiar with and get some videos from youtube. You can use these or search in youtube or google and find your own ways.
Free social network sites. Such as bebo, facebook and myspace. These are good ways to advertise as you can loads of people you don't then hope they drop into your page and like what they see. A great way to advertise on bebo is to go on a highly used group page advertising your page and explaining a little about it in a comment. This is good as so many will see it.
The next method is Youtube. There are different ways that you can do this.
The first way is Hypercam. This way you can show exactly how to do something and viewers can see if the pages they go to are right. It can be done with a voice over so you explaining whilst doing or you can open up a text file and type what you would say.
The Next way is to just film yourself explaining how to do it. I think the best way is hyper cam with your voice over the top. If you search on youtube you will find videos explaining in much more detail about how to make a good marketting video.