The one summer I worked as a spot op, we had cue sheets from which we took our own cues (and controlled our own spot power as well). We were listening in on headset so our cues were based off of or around the LQ numbers. So our sheets would say "LQ25, Tevye, Frame 2, Waist Iris, 3-count" or the same thing but "LQ25+ (He x's through the door)" Our ALD was also our board op, and he was in the same very-soundproof room as the spots (we were in a booth rather than the cats), so he was able to give us the little notes of "tighten up on so-and-so" and such. I think when we got a more complicated series of things, the SM would call a few particular cues (bumps that needed to go with a musical cue, etc).
This summer, I'm now working as a stage manager. We have four spots, and we call everything for them. The spots are controlled thru the board (on subs -- not even thru cues). The gels never change, and the irises rarely change. However, as I am calling from a backstage console, the board op is put in charge of iris-watch. The SMs give their standbys with two purposes: telling the LBO which spots are about to come up, and telling the spots whom they will be spotting and where.
For example, "Standby LQ25 and SpotQ F which is spot 2 on Mabel. She is not onstage yet, but you will pick her up on the up-center platform and she will be in blue." ... ... ... "LQ25 and SpotQ F GO"
Though this seems like overkill, it is actually necessary. Our spot ops are hourly-hired highschoolers, all of whom have a crazy list of conflicts. So every so often, you have a spot op on a performance who doesn't know the show at all. I had this happen on my opening performance this summer. It was the top of the first number after the overture, and the chorus sings a smidge and then there is a solo. I gave the standby (with, admittedly, a bit of lack in detail) for "SpotQ A which is spot 2 on Samuel. He will be USC singing the solo" and I heard a helpless voice from the headset ask, "Um, which one is that? I don't know this show." Gah, slight panic. I had to quickly remember what color jacket/pants he was wearing and quickly describe him -- how do you isolate one pirate from the 15 others onstage before they differentiate themselves? Anyway, I flung enough information at the spot op as possible, and all went fine. But I learned my lesson, and adjusted all of my standbys to include LOTS of info so that in the event that someone forgets to tell me I have a replacement spot op, they'll still be able to take the cues well.