M.I.N.T.S - When do we need a capital letter?

I discovered M.I.N.T.S last year after searching the web for ages trying to find strategies to help children remember when and where to use capital letters (as I find this the main component children forget in their writing).
M.I.N.T.S has worked fantastically in both the Year 3 and Year 6 class at my school (I haven’t got round to giving one to the other teachers yet, woops!) as this poster is a constant reminder for children. When peer marking, I often hear children say, ‘XXX, you haven’t remembered your MINTS!’ etc.
I was also thinking of sticking a mini copy of this poster in the front of children’s English books so that they can refer to it this way too. I have one poster stuck on my whiteboard and one by the English resources.

Hope this helps :)