Just two other quick tricks, in the sort of prevent a rookie mistake area.....
1) If you "think" you can not find your buddy, do not forget s/he could easily be above you. I once did a beautiful barrdl roll underwater and pivoted right around my "lost" dive buddy. {I found out he was under my tank the entire time when I grabbed a roof of a submerged car and he kept going into my field of view from the current about five feet above me.
2) You might want to keep the consule in your left hand just as reminder to check the thing every once in a while...