these tips are for overnight ferries between sweden and finland. or the return journey.

• always always always get a cabin, always
• make sure you have enough reading material
• make sure you have companionship
• avoid watching the karaoke. listening to it is bad enough
• never use the “air seats” as sleeping quarters, the use of the word “air” implies “comfort” in my mind, not anymore. these seats are like concrete and you cant sleep on them no matter what. they are a good place however to watch two drunken men fight.
• prepare to meet incredibly drunk people. there are two types: drunk middle aged men, and drunk teenage girls. this can provide entertainment as one of those groups chases the other one around at 3am after the disco closes.

they are pretty cheap though, and do have cheap alcahol and they are pretty strange which is good. just make sure to have a cabin and enough distractions.