Fold a string into a triangle
Charcoal, 25 22 21 bytes

≔÷Ｌθ⁴λ↙…θλ→✂θλ±λ↖✂θ±λ


Try it online! Link is to verbose version of code. Simply slices the string into three parts and prints them in the appropriate directions. Edit: Saved 3 bytes by using integer division and slicing. Saved a further byte by using CycleChop instead of Slice for the head of the string. Edit: Charcoal now supports drawing arbitrary text along the edge of a polygon, simplifying the code to 12 bytes:

ＧＨ↙→→↖⊕÷Ｌθ⁴θ


Try it online! Link is to verbose version of code.