So I see the pros (M5 and TSM) have Ignite,exhaust, etc. on the left and flash on the right..

Do you put flash on the left and something on the right?
Or flash on the right and something on the left?

Press D to damage
Press F to get the $#@! outta here.

^^^^^^^, that's what this thread is asking about!
But of course this doesn't matter if you have it key binded to another key or gaming mouse...

D for Damage, (Ignite)
F for Flash! (Flash ofc)

I started off playing Morde, so I took ignite on F so I could combo it with my ult easier, I guess it has stuck with me since then.

I actually put flash/ghost on R and whatever else on F. I use 1234 instead of qwer, and I was tired of being dumb and accidentally flashing with F when my thumb is resting on it.

Yeah I heard WoW players like to put qwer on 1234

Flash on the left because it's closer to my fingers and ignite on the right to finish them off

For me I always had escapes on F (ghost then eventually flash) and Ignite/Exhaust on D. Just how I always had it set up /shrug.

Switch hotkeys to T/Y so its Q/W/E/R/T for damage abilities and Y for an escape