You will need a day back pack (ideally with waist straps) to carry what you need for the days walk – a warm layer, water, sun cream, sun hat, gloves, warm hat.
For the porter to carry, if you have a large travelling backpack, that would be ideal. Otherwise, you can have suitcase and they will arrange a duffle bag for you for the porter to carry your things you need for overnight. You will have 7.5kg each to be carried with a porter.
Ref sleeping bags, you can borrow from the company we work with on the ground if you do not have one, but they are not sanitized in between usages, so maybe a sleeping bag liner (cotton or silk) would be preferable.