Does either team winning benefit Texas? If yes, I root for them.
If there is no benefit to Texas, is there a heavy underdog? If yes, I root for them.
If there is no benefit to Texas and there is not a heavy underdog, I do this:
Army vs. Navy | whichever has the best uniform that year (usually Navy)
Alabama vs. Auburn | least amount of historical relevance
Michigan vs. Ohio State | least amount of recent success, and I generally find Ohio State fans to be way more obnoxious
USC vs. Notre Dame | recent flip for me due to the Riley factor
Florida vs. Georgia | Florida feels less offensive than most SEC schools
Miami vs. Florida State | PTSD from 1991 Cotton Bowl is still there
Cal vs. Stanford | Directors Cup impact
Oregon vs. Washington | Phil Knight factor
Arkansas vs. Texas A&M | I loathe Arkansas, but I would be fine with A&M losing every game in every sport forever
Mississippi State vs. Ole Miss | Not sure why, but it's how it usually goes for me