The two most popular methods of promoting a website have to be SEO (Search Engine Optimisation) and PPC (Pay Per Click). These two methods vary differently from each other in terms of how much it will cost you to initialise each project and how long each will take to produce results. If you have a big enough budget then it would be favourable to combine both into your marketing plan as having an SEO and PPC campaign side by side can make your strategy even more effective as instead of hindering each other they actually complement and work well together.
So which strategy should you choose? Firstly you should be asking yourself the question - how big is my budget and how fast do I need results? With SEO the main benefit is the cost, as you don't actually have to pay anything as most of the work is done on page and the off page work that is carried out can be obtained for free if you know what you're doing.
The disadvantage to SEO is the time it takes to actually see results and an increase in traffic as the work that you undertake when performing SEO takes time to be analysed and ranked in the search engines.
Realistically depending on how much SEO work you actually perform it can take from 3 to 6 months to start seeing any real results. It is also worth mentioning that SEO is only free if you have the knowledge to undertake the work on your own otherwise it can be quite expensive having an agency or consultant carry out the work for you.
In relation to PPC you can see results almost immediately once your listing is posted. The problem with this though is that results can come and disappear just as quickly as once your ad is terminated then you obviously lose the subsequent traffic that it was feeding to your site. As for the cost of running such a project, depending on the size of your website and how many visitors you're planning to attract, PPC campaigns can run into the thousands of pounds.
The cost of running such a campaign is also dependent on which type of PPC campaign your conducting whether it is a pay per click (where revenue is generated for every click on the link) or pay per action campaign (where revenue is generated for every actual purchase made on the relevant site).
The best strategy that you could realistically perform would be to run a SEO campaign alongside a PPC campaign and if performed with success your website should dominate the SERP's (Search Engine Results Page).