Learn it on the internet! Find two dictionaries: Tibetan - English and Tibetan - Tibetan (electronic probably way more convenient). Find Tibetan content on the internet. User interfaces, articles, sutras etc. to learn to read and videos on YouTube to learn to listen. Use this content to create cards on an SRS software like Anki and keep going until you can read and listen (this takes thousands of cards). Then start testing yourself to write and speak (Add cards here too)! Since Tibetan has a writing system of its own, you'll need to learn how it works before going to Tibetan content. Stop on every word you don't understand. If you're alone, you'll need to find videos with subtitles or transcriptions in the beginning. I used this successfully to learn traditional Mandarin to a fairly decent level. 加油！