what blessing in general how to go to mikva ? what are the general laws or blessing?

ב"ה Shalom I think I had a similar question not too long ago. For a man, going to a mikveh today, there is no real requirement. It is only for added piety and purity. Therefore, there are different customs of when men go to the mikveh, daily, before Shabbat, before Rosh Hashana and Yom Kippur, before the different holidays etc. Since there is no requirement for men, there is no Bracha said. All the best