Being a publisher can be rewarding but there are some things that come with it that are downright bad.
With great power comes great responsibility. You are the boss (or one of the bosses), you need to make sure contracts are done, and then fulfilled. Monies, work product, printing, editing, playtesting, PR, art and much more.
There is a lot of work attached to making a product. The hours get long and keeping that in mind the pay gets lower per hour, if you even get paid. During my years of publishing during the d20 era I never saw a dime. To be fair, I did get some things at no charge like costs to go to cons etc…. but I never received any money for any of the work I did. I loved doing it so I was not angry but when monies stopped coming in from devious distributors and my credit cards were used and no reimbursement came in my overall income for publishing 30+ books was a negative of more than $10,000. This is not to scare you but to make sure you clearly know what you are getting into when it is all on the line.
Few things that can make publishing sting less:
Publish in PDF, it is a less expensive market to get into and it is a set channel of distribution and you can track actual sales.
Print on Demand, again no financial costs to print and the quality is so high right now they are doing print on demand card games!
Do as much of the work as you can yourself that keeps costs down and hopefully will let you see some profits sooner.
Kickstart it if it is a big project, you have all the power if you already have the funds to pay artists/writers and to print the book before it is completed, it is a financial and emotional stress reliever.
Ask for help, you will be surprised how freely advice can be obtained, names of good printers, names of good writers, artists etc….
Market yourself, get a name and a logo and start making yourself known.
Next, the ugly.