Hi! I'm Lord Forwind, an Eu4 letsplayer. Anyway here is a quick guide with video link below!

How to form kingdom of Jerusalem as Cyprus by around 1479!
1. Develop Cyprus to around 35ish/ get claims on Mamluk provinces
2. Build transport fleet with lots of galleys
3. Wait for Ottomans to invade and occupy most of the Mamluks.
4. Invade placing troops on the 4 needed provinces
5. Hit mil tech 6
6. Take fort, smash Mamluks armies
7. Peace out and core
8. Take event and win!

See video for more details!
https://www.youtube.com/watch?v=5CPkDwJJees&feature=youtu.be