Actually I've created a list based on genuine experience, I couldn't find the paper but as far as I can remember it goes like this;
-Sewing kit (basic inc. different sizes of needles black&white thread scissor)
-10 pairs of socks (learn how to do skivvy roll for easy stowage)
-10 basic tshirt
-You may take necessary meds with you but hard drugs need a prescription that is carried with you. Also there is a sickbay onboard and a selection of drugs are always carried onboard seriously the ships I've worked before had hospital such that a surgeon can operate with the items and meds provided
-A small kit of personal first aid, sticking plaster etc
-I recommend ebooks/ ebook reader or read on your smartphone rather than print copies for obvious weight related reasons, carrying luggage sucks
-Fishing items no pole needed, a strong fish line, a set of different hooks from salmon to squid
-An instrument, a small one; A harmonica maybe?
-A nail clipper
-Toothbrush and 2-3 tubes of toothpaste
-A shover towel
-One extra trouser other than you're wearing
-One extra pair of shoes other that you're wearing (plus safety shoes or whatever special footwear you'll be wearing while working onboard)
-A thread sizes half of your pinky, not to neck yourself but it comes handy time to time you'd never know.
-There will be cigs onboard but they're limited to one or two kind if you're lucky even 3 but nothing sort like menthol cigs or anything like that so beware
-There will be soap but I dunno take 1-2 bars with you just in case
-A photo of Führer (pic related)
-Weather protective clothes; varies by the area and season you'll working and again reduce the size of items only take what's utmost needed
-A selection of useful apps that'll be working offline on your smartphone
-I do not recommend to take food or junk food with you, only adds up weight and they'll be run out fast so why bother?
I hope these will be helpful.