i agree with previous comment, if you are offering SEO services then you should know how to generate traffic. If you don't then you are probably in the wrong business
I think he is in learning phase and he started offering SEO. I would say that first of all, optimize your own site, know SEO practically, because it is too different when you read in forums, ebooks and when you do it yourself..
Of course SEO is very important in monetizing websites. Applying different SEO ideas and techniques will surely made your website get ranked
I would like to tell you that if you want to huge traffic on you websites then you have to update good content on your site in daily basis and nothing else.
Make blogs about SEO, this will have serveral advantages; 1. You will learn more about SEO itself. 2. You can eventually offer your own services to your readers, because you have your own blog readers of your blog will find you more trustworthy.
make a followers in bookmarking site and social natworking sites. then post a link of your site and get huge trafic and backlinks on daily basis
There are many different ways. SEO definitely would help, having quality content on your site is a must. It gets readers to keep coming back. You can do some advertising. Try posting press release on craiglist, its free anyway you might make a few sales. If you got a good landing page try traffic exchange like easyhits4u. Obviously the last 2 are free methods, so I wouldn't expect a whole lot of sales being made. But its definitely worth a try in the beginning to make some sales. Once you have some sales I would reinvest the profits into more proven methods such advertising through PPC and getting high quality articles written by professionals. I hope this helps. Good Luck with your business.