Hi there,

I am primarily a software engineer, but I did get the challenge to get paid once to test and learn all about this, and since then, I do end up helping out with others websites (Not selling myself honest heheh)

Now I tend to want to hold peoples hand through the process, show the pitfalls and the legal (non black hat) tricks for them to understand what they are doing for the long term. Plus if they go and do the legwork with the backlinks and blogdirs and wotnot then it saves them paying me top wage to do what a gimp with a limp could do.

Some early advice I can give to you is, get Google Analytics and Webmaster Tools (sitemaps and keyword search reports) set up for yourself. Seeing as Google is the main engine you are going to try and hit then you may as well use their reporting tools to steer you in the right direction.
Also ----- gives a good all rounder report on how visible you are on some of the nets important listings. (aaah cant post links yet, but its SEOMOZ google it)
A blog thats updated at least once a month with intelligent links (good anchor text) back to your site can never hurt either

Umm heheh I can run on for ages about hints, maybe I will come back to this post when you have done that if you want me to, but - oooh, also make sure your website ISNT in frames. You dont want that, that is a definite no no, and if theres flash then search engines still have trouble reading .swf files so you will want html helper text to explain what is in the flash.
I guess going for the W3 XHTML 1.1 validation and CSS validation and you will be fairly future proof.



But yeah dont pay others if you have time to learn a bit and get control of it yourself as it is a long term thing that needs more than a one off effort. I tend to get requests from the people that have spent 15K with some company that shunted them up to page 1 for 3 months and then ignored them so they went back down to page 10.

Good luck, and before you start, decide on your top keyword/keyphrase searches (the searches that paying customers would type in to find you) and do some testing on your current positions so you can repeat the test once a month and see if your methods are working or not.