This is a really bare bones post that I am putting up for the DNA sig to reference tonight. I will add more as the need arises.
You really need your family tree attached to your test kit wherever you post it. A gedcom is a pretty universally accepted format to accomplish this.
I have successfully created gedcom files by exporting my direct line data from my Legacy program. I believe you can also do this from Ancestry (I don't know the process there.)
Once you have created the gedcom, you need a way to view to be sure you are not publishing a lot of information that you don't really want to give public access to. I like to restrict mine down to names, date and location of birth, date and location of death. I also like to restrict the details of my immediate family and my parents generation.
Once my gedcom is created, I scan it for problems using a free program called GenviewerLite.
Here are some screenshots of the program.
Family view:
Here is the individual view:
The view allows me to see if I have removed enough detail from the immediate family members that I am comfortable displaying them online.
GenviewerLite and the full featured Genviewer are available from mudcreeksoftware.com