I am right-handed, but do my text on the right and my blocking on the left (or the backside of the previous page). I put a number by the text and then the corresponding # gives the blocking. As things are added, I do the same thing as with Qs -- 1.5, 1.7, etc.
I use the same script/score through the whole thing -- so my Qs go on the right side of the right pages. If there's a specific word or place the Q goes, I'll write that in on my standby post-it.
When the show goes into tech, I know it so well I'm not really necessarily following the text itself -- it's like I have the page itself memorized, so I know where things are on the page as the actor is speaking/singing (does that make sense?) So with my Qs in the right all in the same column, I can scan down a page easily to see what's coming up.
Except when I'm at the ballet -- and then all I've got is a score and the Qs just get sprinkled throughout the music where they're supposed to happen.
Even though they're bigger and huger in every aspect, a ballet is easier for me to call because I know it will always be the same. the music is not suddenly going to change from night to night, whereas actors are subject to drop a line, a paragraph, or even a whole page!