I have visited this place last August. Since I was still in NRW after a different adventure and I had this place on my radar for a while after reading positive reports from Wanking, I decided to give this place a chance.
And I am sorry that I did, because this was one of my worst experiences ever. It was like a freak show: I saw an obese hunchback (woman) of about forty years old, a thin, tall woman in her late twenties who had a normal face and that I initially wanted to fuck (untill she smiled and I saw her teeth: half was gone and the other half was rotten black: WTF

I am not putting my dick in there!) and a drag queen whom stood (with heels) about 2 m tall and was about 100 kg. (I entered the building at the same time as the drag queen and in the apartment building on the other side of the street people had there windows open and were watching and laughing about the freaks entering Blue Heaven.) Besides there were a lot of grannies and people that looked retarded.
It is a relatively small swinger club (though the building has more depth than one would expect when standing outside) in a residential area (there are some shops and restaurants nearby though). Moreover the club is quite outdated and dirty (used condoms are all over the place). When you enter you have a small bar area and the locker room, then a small room where you can get some snacks (given my general impression I didn't venture eating anything) and then on one side a small BDSM-room and on the other side another small room. Further down the hallway there is the main area where you can sit and there is (among other things) some kind of high bed/table where a woman can lie down on and get fucked. And there is a large screen with porn. When you walk further you will find the showers.
When I arrived I saw a young woman (mid twenties) lying down on the table and getting fucked (she was one of the few women present that looked decent; she did a rush job shaving her pubic hairs though). There were so many men around her that I didn't get an opportunity to fuck her unfortunately. Shortly after I arrived she went off the bed and then left the club.
There were a few worn down grannies that let themselves get fucked by everyone: they also had many men around them willing to put there cock in, but I couldn't put myself to it. There were 2 or 3 women from couples that I wanted to fuck, but unfortunately they stayed in the bar area or only went with other couples.
I wore a dark boxer short and had my slippers on, but I also saw people with a t-shirt on and with dark shoes on. I also saw people barefooted, but I wouldn't recommend that. Some men even walked there completely naked. In the bar area I saw some people that had clothes on (sexy clothes though), but they seemed to stay in that area. So, almost everythings goes.
You can park your car on a nearby residential parking area. I paid about 40 euro (food and drinks included), had my own locker, got a towel, condoms lie at specific places (not very abundant though, so make sure you keep one in your boxer shorts in case an opportunity presents itself). And like I said before the place is shabby and unhygienic and most visitors are down right mingers.
Therefore I will not be visiting this place again. I thought about visiting a similar place (small and cheap swinger club), namely P3 in Bochum, but after my experience with Blue Heaven, I am rather reluctant to go. I stick with HÜ/GB parties at regular, bigger swinger clubs in NRW: because they have much more to offer (sex wise, but also regarding food/drinks and sometimes a sauna, bubble bath or even a swimming pool), often have a much better interior, attract a different crowd and they often have a special low price for HÜ/GB parties (so you pay about the same, or slightly more than you would at Blue Heaven, but get a completely different experience).