Karlskrona is a city Sweden.
E22 West towards Malmö/Helsingborg/Göteborg
Take bus nr. 5 (towards Nättraby) from the city centre (Kungsplan) price 20 kr/2 euros. Jump off at the stop "Motellet". I have been standing at this bus stop with a sign, 2 times and have never had to wait more than 45 minutes. I use to have a sign saying Sölvesborg or another town on the way beacuse sometimes people doesn't stop if you write Malmö because it's so far away. There is not so many service stations along E22 and some of them are off the motorway (in Karlshman and Kristianstad for example) but it's better to stand there than along the road. If you are going to Göteborg make sure that the driver is gonna take off on the exit towards Göteborg because there is no service station before it. It use to take me 5 hours to hitch between Karlskrona and Malmö.
North towards Emmaboda
While hitching in this direction, we were going between two gas stations with a sign. We had no luck whatsoever there and stood there for half a day. We finally gave up after getting the advice to walk the road up north and stand after the roundabout instead. This worked and after about 30 minutes we had a ride. So if you're going north, passing the roundabout to get cars from other directions and ones that are going in the right one is definately an advantage compared to the gas stations. Another thing we learned there is that at about 20:00 there are ferries coming into Karlskrona which results in some trucks stopping to fuel at the gas stations. But we had no intentions to stay that long to find out.
Hitching from the Gdynia Ferry
On a tuesday morning we came with the ferry from Gdynia 07.30 with little hope of getting a ride and no knowledge of the city. Deciding to just start hitching along the way from the ferry we walked along the road. We carried two signs, 'Halmstad' 'Göteborg' wich we hoped would get us all the way to Gothenburg or at least to road E6. After only about 15 minutes we got picked up by a truck going all the way to Gothenburg! If you try this you should probably choose either a common travel destination that is along the way to your final destination or be really lucky. This probably doesn't work as well with the smaller swedish cities so be creative! The truckdrivers was the only ones who responded to us standing on the road side so make sure you have a sign big enough for them to see.