Welcome @ Khecari Devi Ashramam! More coming soon… describing the Ashram and what is going on here.
English Material: A booklet about Khecari Mudra is available in English, as well as a paper describing the use of the pilous system as a yogic tool. See the Menu « Materiel/Articles ». On the associated youtube channel, some videos in english also (Menu « Materiel/Videos » to reach the youtube channel). Translations of the other texts is underway, stay tuned! Any help in that process is more than welcome!
All the best, Mahesvara Yogi.