It has never been more important to understand how visitors arrive at your website and how they behave when they get there. That's why we always applaud our website design clients who actually come to us with Google Analytics already set up on their old websites. This allows us to not only show traffic and conversion data for the newly optimized sites we develop, but with previous site GA stats, we can compare to historical data to show progress. Additionally, knowing that clients already see the wisdom in having Analytics installed tells us they understand the value of making data-influenced decisions about their website and online marketing efforts.
Sadly, even these clients (who are an extreme exception, by the way) are rarely aware of some of the more advanced settings that can help ensure data is as pure as possible. One of these advanced settings isn't advanced at all, but can go a long way in helping to provide a more accurate and comprehensive understand of real website visitors. The simple process of filtering out traffic from their own IP address prevents internal traffic from skewing metrics in any unnatural.
But enough with the why, let's get to the how...
Click on "Admin" in the newly designed Google Analytics navigation menu:
Assuming you have full administrative access over the account (not just the "property" or "view"), you'll be taken to a screen that looks like this:
Here you can click on "All Filters" to add/edit filters for any of the sites listed within that account, but even if you only have admin access over the individual site you can still add/edit "Filters" (as you can see in the circled sections above).