i have two macros

Transpose to ice
/macroicon "Transpose"
/ac "Transpose"
/chotbar 3

Transpose to fire
/macroicon "Transpose"
/ac "Transpose"
/chotbar 1

i have the fire skills set up on hotbar 1 in the R2 circle/square/triangle/x and the first macro on the R2 d-pad but you can put it wherever. then on hotbar 3 i have my cold spells and the second macro on hotbar 3 in the same location. Any abilties that i plan on using no matter the AF/UI currently up (Thunders, scathe, etc) i place in the same location on both hotbars. If you want to use different hotbars just change the numbers. I have a similar setup on my summoner to have it change hotbars when i go into dreadwyrm trance, with deathflare being macroed to switch me back, and on my scholar with cleric stance to have my heal hotbar and a damage ability hotbar. Had to come up with something since the arcanist jobs can't fast cycle through hotbars with a pet out.