Best bet with lettuce is to sow little but often. They run to seed very quickly when the weather is hot. The last thing you want though is a glut of lettuce all ready for harvesting at the same time - because you just can't eat it all and you can't freeze them.
I think we have all been there with the lettuce gluts! What I do these days is sow a single seed in a tiny pot (about 5 of them, every couple of weeks) then when they are big enough I plant them out. Then if a couple get eaten by the slugs or whatever there should still be enough to keep us going all season.
Well that's the theory yet I have a load all ready right now but the next lot are still tiny!
