Create Smite Clan / Tag?

Huhu it's your BlauerBison01 again

I discovered in the settings at Smite on my Ps4 that you can set whether the respective day should be before or after my gaming name.

So I finally concluded that you can set a day somewhere or create a clan / group with a day, but I don't find it or don't know where and how.

Can you help me?

Must under Social> Clan and there you can actually create one and specify a clan day.

Where can you find "social"?

There's a clan tab in the menu. Otherwise at Profiles. Before 2018, this was called the Social Tab.