Here are some specific examples of what your first steps MUST be when creating any new website... regardless to the subject matter.

In this example, let's create an affiliate marketing related website. We’re picking this topic at random because I do some things in the affiliate marketing market, so it makes things easier for me to explain to you. Before we start creating and collecting content for the website, we need to do a little keyword research. This is VERY important and should not be skipped. To do our keyword research we need to, first, visit a few websites.
The first of which should be http://ping.fm/EPH2u
Finding the best keywords are very important because these words are words that will be used by potential customers to find you. In fact, this is how we lead the customer to us and not to someone else. This is anticipating words the customer may type into their browser to find what they are looking for.
Goodkeywords has a very good keyword tool, and best of all it's free!

Once we've downloaded this software, we can enter the most generic keyword for our website into the software. In our example, our keyword would be "affiliate marketing".
Type in your generic keyword in the subject line of Good Keywords and it will return a list of related terms. The "words" column will show us the top 100 search keywords that contain the words "affiliate marketing".
The "count" column will show us how many times the specific keyword has been searched for in the previous month within the Overture.com search engine. Generally, you can multiply that number by 8, in order to estimate the number of times that keyword has been searched within Google for the previous month.
This step is critically important because we need to know if there is a market for whatever topic we choose to sell. This tool will quickly show us if people are looking for what we want to sell!
Please DO NOT start off by optimizing for the keyword
Why, you ask? If a keyword is searched that many times in Overture, then 100 times out of 100, the competition you will have to outrank in Google will be extremely overwhelming.
Not only is the competition overwhelming, but think about it... How targeted is the keyword "affiliate marketing" anyway? Not very targeted at all. Someone searching for the keyword "affiliate marketing" could very well be looking for free information on affiliate marketing.. They might be looking for the definition. It's really hard telling. Chances are, they're not looking for anything specific.
The keyword "affiliate marketing" is not something you should try to take on. It’s too broad!
For a brand new website, or one you're just beginning to optimize, it's better to select more specific "long tail" keyword phrases. I'll talk about this a bit later.