OK, I'll have a go.
Pack in a backpack , no stupid wheels or handles. Hand luggage is your day pack. Remember liquids , gels and pastes rule.
Passport, tickets, insurance , ehic if europe, medication.
Money, bank cards, credit cards - all providers told you are away
Toiletries - toothbrush, paste, shampoo, soap,shower gel, conditioner
1 big bottle suncream, buy more abroad. Insect repellent ditto
5 pairs knickers, couple of bras, socks
Shoes: hiking boots or shoes , pair trainers (travel in these), pair flip flops
Two pairs convertible quick dry trousers
Hiking tops
1 light fleece , 1 heavier one
Nightwear
T shirts/tops/ vest tops
Swimwear - board shorts , bikini tops, rash vest, sunhat
Gadgets as you can be bothered. Something to take decent photos with.
All in same colour palette - no white or black.