How do I get tickets to the Domus Aurea in Rome?

The Domus Aurea is open to tours only on Saturdays and Sundays. No exceptions. Tickitaly is a reseller. Here's the direct link. Be sure to book one of the English language tours.
https://www.coopculture.it/en/heritage.cfm?id=51

FYI, there are other cool underground ancient sites if that one doesn't work out for you. Check out the Domus Romane: https://www.palazzovalentini.it/domus-romane/index-en.html

Get tickets only on the above coopculture site, The Domus Aurea is an active archaeological site. Monday through Friday it's still very active

Thank you so much for your help. I have to see this place!!

Szarate, what Dario meant by, "The Domus Aurea is an active archaeological site. Monday through Friday it's still very active" is that archeological excavation work occurs during the week and they do not allow visitors during that time. The only days you can visit are Saturdays or Sundays, and only with a guided tour. For tickets, see the coopculture link Michael provided above.

I will be in Rome in late April, and have been watching the Domus Aurea online ticketing site for a while. It appears that the site will only let you buy tickets for the current month, meaning now you can buy for English tours at several times on Sat Jan 25 or Sun Jan 26. But the calendar will not yet advance to February so you can buy future tickets. If someone has other related knowledge or experience, please share. Maybe there is more flexibility if you phone them..
PS: On the weekends, I believe the guides are archeologists, or maybe archeology students, who are involved in the dig during the week.

If you go to the Coopculture website Michael linked above, you can select "Buy tickets". When you get to the calendar, just click on the arrow to the next month. Currently tickets are available through the end of March. (Tours are not available on two weekends in early March.) I purchased mine a couple of weeks ago; the transaction went very smoothly. If you call or email you may be able to find out when tickets for April and beyond will be released.

Thanks Den, that little arrow sure is tricky, at least on my iPad. It took me about 15 tries to get the month to move, but sometimes it seems to respond.

To clarify, Tickitaly sells tickets. The tour is operated by Domus Aurea's archaeology staff. All the tours are lead by folks who work on the site during the week - which is why tours are only on weekends. It's cold inside, so if you're going in warm weather, take a jacket or sweater!