Then you select "Ancestry Finder"
The first time there will be a survey for you to fill in. Fill this in, even if you dont know who your grandparents are. "Unknown" is an option. By filling in the survey you will appear in other peoples AF. If you are not a Public match :( you will appear as Anon. But really, do the world a favor, and be a Public match!
Now, this is what my AF looks like at the initial settings:
So, if you're reading this just to learn how to download your AF, your done!
AF at its initial setting shows you the %s of your chromosomes where you match with a person who reports that all 4 of their grandparents were born in the same county. You can see mine shows that 1.6% of my chromosomes are matched with a person with 4 grandparents from the UK, and 1.3% from a person with 4 Irish grandparents. I would expect as the database grows at 23andme more of everyones DNA will be shown in this chart. I am certainly more than 1.6% UK ancestry and more than 1.3% Irish ancestry.
If you click the "Show Advanced Controls" above the graph, you can change things to show people with 1, 2, or 3 grandparents from the same country, and change to show matches primary from US, Canada etc. You can also change the segment size to smaller or larger as the threshold of match required to show on the chart. By selecting 1 grandparent you will see a lot more of your DNA.
Here is what mine looks at for 1 grandparent setting, when I show matches from the US etc:
Not surprisingly, I show a great number of US matches.
Very close relatives (ie a parent) dont show on AF, or they would block anything else from showing. At this time I find the graph interesting, but not overly useful. The downloadable file is another matter, I find that VERY useful, and will explain how to use it in another post.