When making randomized triggers, I find it best to start off with the biggest number and go down to the smallest number.
Lets say you are using 4 triggers. 2^4 = 16. So you have 16 possible outcomes.
In this case, I will use binary to represent the switches state.
1=set, 0=clear.
I usually start off with all Set, and slowly make my way down towards all clear.
Here we go:
1111
1110
1101
1100
1011
1010
1001
1000
0111
0110
0101
0100
0011
0010
0001
0000
There's what you can use to easily figure out which triggers you have or havent done yet. Simply 'strike-out' the number or put a check mark beside it.
I'm so bored that I have already started doing 2^100... that means there are 1,267,650,600,228,229,401,496,703,205,376 possibilities. And remember, Starcraft has 256... so can you imagine?

I have no idea how that number is 'said', so lets say ... a little over '1 million trillion trillion'? LOL... i'm such a nerd.