From Longman Dictionary of Contemporary Englishrun before you can walkrun before you can walkto try to do something difficult before you have learned the basic skills you need A lot of language students want to run before they can walk. → run
Examples from the Corpus
run before you can walk• I think too that she wants to run before she can walk.• Just don't try to run before you can walk.• Try to be honest with your use of the table and don't attempt to run before you can walk. 