A few general points that you might want to consider:
- employ guides who know where they are going and have up-to-date knowledge of the desired trekking route. For obvious reasons, when trekking in Zanskar I always use a Zanskari guide or horseman. If you are planning to visit Zanskar, and you want to contact a Zanskari guide but you don't know how, then check out www.trekzanskar.org
- ensure you have changed foreign currency into Indian Rupees before heading into Zanskar. There is no money changing facility in Padum and whilst many Zanskaris have now seen a 50 or 100 USD note it's awkward for them to change. It's really embarrassing to end a trek and not have enough money to pay your guide or horseman; more importantly you owe your staff some cash. It's no longer necessary to carry a suitcase of small denomination notes (the economy has moved on somewhat), but by all means carry some, the pan-Indian 'no change' phenomena is alive and well in Zanskar too!
- make the most of the choice in the shops in Leh or Manali. There are food and general provision stores in Padum but choice is limited for more Western-style luxuries, especially towards the end of the summer trekking season (and in winter or early spring before the Pensi La has opened). I usually carry a few choice items like Marmite, Nutella and Western Style Meusli (which, if nothing else, has amusing marketing on the reverse of the box). If you are concerned that you wont be contributing to Zanskar's economy then don't worry, many of the shops in Padum are not owned by Zanskaris. You will probably make a greater contribution by employing Zanskari trekking staff.