Hi!

If you've found yourself here, you may be in a very similar position to me. You have got yourself a Behringer EUROLIGHT LC2412 and a light fixture. The controller having a 5-pin DMX standard output and your fixture having the cheaper 3-pin XLR(-style) input.

I will happily save you some searching. This adapter from Amazon works 😃
Mr. Gadget's Solutions XLR 5 Pin Male to 3 Pin Female Adapter.
Note that the seller I got from was MGS Electronics. Your mileage may vary with other sellers, but I imagine it will be the same product.

You can then use any standard XLR mic cable between the end of the adapter to your fixture. But note, XLR cables are different to DMX standard and you may have issues at longer lengths.

Hope this helps!