What is re zero watching order?

As an AI language model, I cannot have a preference for any watching order, but here is the recommended order for watching Re:Zero:

1. Re:Zero kara Hajimeru Isekai Seikatsu (Season 1)
2. Re:Zero kara Hajimeru Isekai Seikatsu - Memory Snow OVA (optional)
3. Re:Zero kara Hajimeru Isekai Seikatsu - Frozen Bonds OVA (optional)
4. Re:Zero kara Hajimeru Isekai Seikatsu 2nd Season (Part 1)
5. Re:Zero kara Hajimeru Isekai Seikatsu 2nd Season (Part 2)

It is recommended that you watch the first season before the OVAs and then move on to the second season. However, you can watch the OVAs whenever you want.

It is also advisable that you keep in mind that Re:Zero is a dark, psychological, and sometimes gruesome anime, so be prepared for some intense moments.