In colloquial speech, this is almost always pronounced as zhuǎ. However, in more literary phrases, such as chengyu, it can sometimes be pronounced as zhǎo.
Mnemonic
[zhu-] George Costanza is in the [3] basement of the [-a] auditorium where he is looking for some 爪 claws that he will use in his play that he is starring in, Fat Man with 爪 Claws. He finally finds some and puts them on, then laughs as he says aloud a line from the play he has been rehearsing. "Everyone respects a fat man with 爪 claws, even if he is balding!"