It's kind of like being a tracker who learns the difference between a deer print and a rabbit print, and how long it has been since the animal was on the path. For us, how long it has been since our ancestor was around.
If you are an adoptee who has discovered one parent but not the other and know someone on the "known side" who will also do the free transfer, this can help you "divide" your maternal from paternal lines.
Here are some basics to get you started. Log in and you will find the landing page.
There is a place called "About Me" under the heading "Manage Personal Information" where you can tell your matches about yourself. If you put nothing else here, add your GEDmatch kit number. You can also say something like, "I need all the help I can get." There are some people who will.
This landing page is also where (if you took your test here) you can download your raw data for transfer to other sites. It is also where you find the Matrix tool (I'll get to it).
If you don't have a tree make one; even if it just shows you, and bio mother unknown or bio father unknown. Times have changed and most of your matches are willing to help. This is a nice way of asking for it.
Click on the "My Family Tree" tab to fill it in. If you have a gedcom you can upload it by clicking on the gear and uploading. It's that easy.
You can click on the Matches tab to view all your matches. Your closest ones will be at the top of the page.
At the very top of the page on the right, you will see the most common surnames among your matches. This can be a little deceiving if someone has added a bunch of one surname in their tree or have the surname listed in the place where you can fill in their list of surnames. It can also act as a clue to what your paternal surname might be especially if it is not a common surname like Smith, Brown, White or Jones. A bunch of Shoff surnames would be unusual. You know your match has a tree if the little tree icon is blue.
When you search surnames your match page changes to show people with that surname identified somewhere in their tree or their surname list.
Next, try selecting the person at the top of your match page by checking the box next to their name and select "in common with". Select the first four people that come up on this "in common with" page and click the chromosome browser. (You can look at five people in the browser at the same time but only add four right now.) Give the browser a minute to populate.
Look at the chromosomes and see if there is a colored coded stack of people who share on the same chromosome and overlap in the same position.
Now, on the left of the chromosome page in the "Filter by matches" box use the pull down menu and choose Name. Enter the name of the person who you checked for "in common with" and click their box that will be next to their name. Does that person show up in your stack? Once you have some people stacked up in the same place and chromosome write down their names. Check the rest of the people on the "in common with" page to see where and how they stack up with each other. You might end up with a couple of others who stack up on a different chromosome. That's great.
Now go back to your landing page where you find the link to the Matrix tool. It may take a minute for your match list of names to show up. When it does scroll down to find the people's names you wrote down who stacked up. Click on their name and choose add. If you get a blue box with a check it means they all match each other. This highly suggests a triangulation which means you share a most recent common ancestor (MRCA). You can adjust the names up and down in the Matrix until you get a neat square of matches. Some people may match most but not everyone; that's okay. It could be where their DNA recombined, but you want at least three who match each other. If the don't have a tree up write them to see if they have a tree. (You can tell them how many matches they have with you and how many matches would probably contact them just from your match page alone.)
You can click on their profile picture or icon to see their email address.
The little note pad with pencil is where you can add notes. Be sure to save because the notes will dissappear if you don't.
Using DNA Painter in conjunction with FTDNA is great. I keep it open in another tab when I am using FTDNA. I use the cM tool V4 because it gives me best odds of how we match.
Enter the total amount of cM in the little box on DNA Painter. (Round it to an even number.)
Look at the grandparent umbrella to see which generation of grandparents you most likely share. The boxes will light up for your most likely relationships. If your match has a tree (remember it will be blue) click on it and in the upper left click on pedigree view then count back back from their parents to grandparent, to great grandparents to great-great grandparents or however far and write down the names (I do screenshots and use microsoft paint to add my matches name and amount of cM's they share with me) of the grandparent level my relationship on DNAPainter says I should share. (Also a good time to make a note on their profile as to suggested grandparent generation.)
I also use MS paint to draw a circle or box on the screenshot around the grandparent level so I can study these sheets and know where to look when I am comparing screenshots of matches for a most recent common ancestor (MRCA). A MRCA can be a pair of grandparents. I know. I thought it shoud be MRCAs for a long time, but sometimes it ends up being only one grandparent (people die and remarry or they sometimes mate outside of marriage).
When in Family View on the tree tool you can click on "show details" which will reveal birth and death dates as well as locations. (If only they all did.)
Please, everyone upload your raw data to GEDmatch and invite your matches to do the same. If you do have a triangulation you may find more from other testing sites and grow your triangulated group.
Finally, when contacting your matches, if you find someone who is adopted, be sure to let them know who the most recent common ancestor is that you share in your group. People who are adopted can help you by searching their match list to see if they can find more information by searching these surnames among their matches.
Finally when you find or know a most recent common ancestor build your tree back (if you are adopted you can enter private for either parent back the distance to the MRCA (it doesn't matter that you don't know which side they are on at this point (you can rearrange later if you need to) and add your match's tree branch all the way to your match. Then click on the link tool. It brings up your match as you enter the name. There is a little chain link you click on to link them. If you add the branch on your maternal side FTDNA's program will light up a bunch of trees with a red icon for maternal side. If you add and link them to your paternal side it will light up most the matches that match your matches with blue. Just remember we don't know yet if this is maternal or paternal. (Unless you do--which is fantastic!)
If you are adopted and are a female and you get lucky and find a female match with over 1330 which is a possible half-sibling (DNA painter will give other odds on other possible relationships) and you share 196 cM of X, you share a common father.
Still having a blast.