How severe is the bleeding?
Is there a large opening where the cyst is?
If you have some Betadine solution this will work well to clean it up. Than apply some Neosporin to the area. Try and trim any hair away from the area. This should be fine until you see the Vet in the AM. I would withold food and water until you see the Vet in the AM in case they need to use anesthesia to remove the cyst or put in a drain. Joan