A method for performing ad scripts without memorizing them: read a line, memorize it, deliver it, move to the next one. Jump cuts between takes make it work. Perfection isn't the goal, just nailing each line.
Chapters
The number one way that I find to read scripts is to look at the script, memorize a line, think about it, deliver it, and then go back, look at the next line, memorize it, deliver it, and then you just jump cut through all of those cuts, which is totally fine. And those ads work great. It's okay if you mess up. No one's expecting you to memorize the entire script all the way through. But I do like to look at it, see what it says, memorize it, deliver. And then I repeat that process over and over and over again until the entire script is done. And when you deliver it this way, it saves you a ton of time from having to memorize or trying to be perfect all the way through. None of that really matters as long as you deliver the line well, and then you go back and look at the next line and then deliver it again.