The gedmatch.com website is a site for sharing and searching for autosomal tests and results. Autosomal tests are tests like FamilyTreeDNA's Family Finder, Ancestry.com's AncestryDNA, and 23andMe's test. gedmatch.com allows searching across multiple testing companies whereas the search facilities in FTDNA, Ancestry, etc. only allow searching for their own customers.

A cousin recently shared this simple set of steps for getting started with gedmatch.com

My longtime genealogy colleague, Nancy, sent me this to get me up & running on GEDMatch fast. It worked for me. You don't need it yourself David, but thought you could make use of it with newbies to autosomal DNA who want to do this quickly without looking it up.

Three Basic Steps to Create a www.GEDMatch.com Account

1. Go to www.GEDmatch.com and create an account. Your account is based on your email (so carefully choose the email you’ll want to use), and a password (known only to you – if you forget it, you’ll need to reset the password). You’ll get your own homepage at GEDmatch, which will list any DNA kits you upload and/or any GEDcom.
2. Go to your DNA company and download your raw DNA data file – note the name of the file and where it is saved (usually your Download folder); leave the file zipped (do not unzip it)
   • FamilyTreeDNA – on your main “Dashboard” page, under the Family Finder section is a link: “Download Raw Data” – click on that; and then click on the download arrow for “Build 36 Raw Data Concatenated”.
3. Log into GEDmatch and upload your raw DNA data file – in top right box, click on “Generic Upload”; then fill in the form; in the last row: Click on “Browse” means: Click on “Choose File” button. Do that and navigate in your PC folders to where your raw DNA data file is, and click on it. Then Click on “Upload”. Wait several minutes for the process to complete and give you a statement that it is finished.