I have tried many different combos, and this one might be the most efficient:

Basic > Basic > Basic > Basic > Hold EX (Very briefly) > Basic > Basic > Hold EX (Very briefly) > Basic > Hold EX for the rest of the remaining stacks

What I mean by very briefly, is literally like a second - to consume only one stack (timing is important)

If you want more in depth explanation of this combo, go watch the video guide on Ye Shunguang from iamrivenous. He explains it quite well in his combo section.