To sell glow in the dark star ceilings at craft, home, and kid events, you typically need a display tent. This dark tent allows potential buyers to actually see how nice glow stars can look.
If you make the tent fun, you can also do cheap advertising whenever kids and parents congregate. In this case, I would suggest you contact several dozen local PTA's to inquire about planned evening events.
Here are some tips on construction:
I highly recommend the $250 carport sold at Costco. At 10' x 30', it is large, durable and easy to set up. The poles are 2" and the tarp material is very thick. Glow Inc has had one outdoors for rain and high winds for several days without a problem. For the price, it is an amazing value.
A 10' x 10' option is the EZ-UP style canopies. Make sure that you get one with 4 walls. While they go up easy, these tend to be a bit small. I suggest you do not but the 15' x 10' version as it is cumbersome to erect. Unlike the carport, these can not survive weather like rain and wind.
A low cost, but hard to erect alternative, is to simply build a frame out of wood and cover it with Coroplast (corrugated plastic) using tacks. Each halloween, Glow Inc builds 250 feet of hallways using this method.
Ceiling and Walls
Paint your ceiling design on white Coroplast sheets and hang it inside using cable ties and/or velcro.
Even if you do not intend to paint the walls, you may need to cover them with coroplast to keep out external light. I prefer black coroplast for the walls. Of course painting the walls adds another dimension
For adult sales, I would suggest that you turn on the black lights when the room is empty and turn off the black light just before people enter the room. For a more automated setup, put the black light on a timer and have it turn on for 30 seconds every half hour.
For kids events, I typically leave the black light on. In this case, it is preferred that the black light shines upwards and that the actual bulb can not be seen by adults standing in the room.
You want to use black lights that do not require holding down a button to turn them on. This allows you to route their power through a power strip or timer that you can control from the outside.
Stage fixture style black lights are durable for transport and can be mounted to a quick release bracket. For a mobile star room, I would suggest a product like the Chauvet LED Shadow.
A lower cost alternative is the tube style black lights, which can be mounted to the vertical poles using cable ties. However, keep in mind that these are easily broken by children.
If you are doing this at a kids event, then I highly recommend that you add something else interesting to the room. I personally like the automated bubble machines. However, you need to make sure that you add some type of flooring to provide friction. Bubbles on grass is like walking on ice. Also, make sure you turn off the bubble machine when the room is unoccupied or you will end up with a big pile of bubbles on the floor. Mount the bubble machine as high as possible.
You can also make one wall a Shadow Wall.