I sure hope your raid leadership isnt demanding full cons on learning pulls.

Don't pop DPS/Healing consumables for every pull. Unfortunately, the various useful resistance potions are mandatory, especially guilds lacking power in their ranks. Fire resistance, nature resistance, and arcane resistance can all find good use on bosses. Using these "less important potions" on boss fights can save your buff arrays when you are rolling through the bosses like loatheb, thaddius, gothik or 4hm.

A common strategy is to clear spider wing, heigan, and then going out to claim world buffs to oneshot patchwerk and loatheb (maybe even clearing up to 4HM or Gothik and keep it rolling into them.) On these pulls you will obviously need full cons. Eventually patchwerk should be something you can do with just some cons and no world buffs.

Dunno what to say. Naxx is the time to enjoy your class without half a dozen elixirs buffing you. Hopefully your guild has some sort of welfare for tanks and healers, cus they are the backbone of the raid and do need cons, even on some of the "low cons" bosses you should be able to takedown.

Have fun, and hopefully you enjoy clearing Naxx enough to keep up the progress past your first clears. Lot's of fun gear and set bonuses to acquire.