Patents are cheap and fairly easy to file - you can get a provisional patent for a few hundred dollars that gives you about a year to test the waters and see if you want to get the final patent. The total cost if you file yourself will be under $2k. Lawyers will add another 5-10k to that, but you don't need them if you're willing to do a little research. The big benefit of lawyers is that they know how to make the patent language vague so it is easily "weaponized."

The next step while you're preparing your provisional patent/final patent is to create a really slick demo to sell prospective licensees.

Once you have a provisional patent and a demo the next step is to actually find people to license to. If you have lots of industry contacts this could involve making a few phone calls, but in most cases you are going to need to work trade shows. Cold calling can work too but it's tough.