How should i allocate income i set aside for covering TAX and GST

HI all im looking for some advise on how i should be be allocating my income i set aside in two separate accounts which i use to cover my GST and TAX.

I have No.1 main account which my income is paid into. 

Then i will transfer a set amount each week into No.2 GST account

And also a set amount into No.3 TAX account

All 3 accounts are with the same bank and account and all 3 are connected with Bank Feeds, i am not sure how i should be allocating each withdrawal from my main account. 

I would be very grateful for any advise on this.

Many Thanks