tack or helitack

Standard tack would probably be easier to learn and slightly more effective at getting you upwind, I would think?

Tack!
It has helped me considerably with both those issues.
I would say learn boom to boom.
Keys for me have been
1 front foot wrapped as far around the mast as possible.
2 rig back and arms straight before moving to give you something to oppose on the other side.
3 front hand right up by the mast, back hand by the back line
4 throw the front hand towards the opposite shoulder (moves the mast down the centre of the board and forward)
5 get low, wide stance and on the new side throw the rig forward
6 keep the feet on the centre line and you can get away with a lot.
7 big rev (sheet in) with the back hand at the finish
8 don't go too early if you are not planing (get the board through the wind)

Practise rig/ foot movement on the beach(bury the fin). The more repetitions the better until the movements are automatic.
Then try and find a shallow flat water spot to practise (much harder in rolling chop)
Watch Cribby do a few www.guycribb.com/windsurfing_technique_holiday0074v01.htm
Do a course. You will save yourself a heap of time! Have a look at the Technique PDFs on tacking on his site (you need to register).
After you have the hang of it you will find it easier on a smaller board as you can scissor the board round at the finish.
Good luck!