There are two very useful tools that I have found on FTDNA. The first is the "in common with" and the second is the "chromosome comparison."
The "in common with" tool allows you to search for people that share DNA with you and another member of their database. Say for example you have a confirmed 2nd cousin on FTDNA, you could then use the "in common with tool" to find others that also match the 2 of you to find other potential cousins. At this point I do not haven any confirmed matches on FTDNA, so I used it in a different way.
The first thing I did was find someone that I shared a good sized segment of DNA. I then clicked on the "in common with" tool and found we had 25 people that in one way or another we share as a potential match. I then used the second tool, the "chromosome comparison" tool.
Using the chromosome comparison tool I found out that 12 of the 25 people we had as common matches matched both her and I at the same area on chromosome one.
What does that mean? it means that at some point in our trees the 14 of us share a common ancestor, or ancestors. Now working together we can try and figure out who that ancestor is.
There is just one problem, when writing these matches I am finding some of them are not understanding what I am talking about when I mention the "in common with" tool and the "chromosome comparison" tool. So I have made the following pictures to hopefully help others understand these tools and how I used them.
If you have questions or something isn't clear, please contact me so I can try and make it easier to understand. Happy hunting!