The Blue Lagoon is definitely worth the hype, even if it is a little touristy. Reservations required ahead of time. You can book them online using the link on this guide. There are a few tier tickets, the Standard or the Premium. We did the Premium Package, which we would highly recommend! We paid $82 USD each for the following:
Entrance to the Blue Lagoon
Silica mud mask
Two additional masks of your choice
Use of towel
1st drink of your choice
Use of bathrobe
1 glass of sparkling wine if dining at Lava restaurant
We liked this package because since it was chilly outside, the bathrobe was very nice to have and the 3 masks made it feel like we got the full experience.
PHOTO TIP: They charge an insane amount of money for commercial photography here, but we asked and they do allow personal cameras/tripods. We just set up our tripod near the closest outlet of the lagoon to the entrance of the pools for a short amount of time and snapped quickly. It's very crowded here so you'll likely have to remove people from your photos if you visit mid day. We highly recommend bringing a Go Pro and Waterproof Case for your phone!
https://youtu.be/h_0w39eiPN8?si=GqnDsLibBWf38jmE