What is the best method to make a Saas profitable?

Hi there I am the creator of 1tools, free tools for everyday needs on the internet. today the website is completely free and without ads, my goal is to simply help people whatever their field of work but I think I need to get some money since there are several expenses (hosting, development, maintenance, subscription to third-party tools, etc.) so I'd like to know what is the most relevant way for you to make this project a little profitable? affiliate marketing ? Google Adsense ? donation ? or other method ? Thanks in advance Yassine