The Texas Young Lawyers wrote a wonderful free booklet.
I would look on their excellent website for information.
The booklet I like is "Pro Se Divorce Handbook"
I believe it was written in 2010 and Texas family law has been modified by the Texas Legislature since 2010 but it's still a pretty darn book FREE booklet
Another of their booklets is What to Expect in Texas Family Law Court which was initially written in 2004-05. Again, Texas laws are modified every 2 years by the Texas Legislature but it is also a good book.
Their abbreviation is TYLA.