A Beast-Trait (BT) +jnote should describe the circumstances that will trigger your Beast. Beast-Traits that require +jnotes are; BANE, BOUND, FETISH, ITEM, PHOBIA and TOUCHY.
When writing these +jnotes make sure that a Beast-Trait will realistically be triggered during RP. Staff will disapprove triggers that your character is unlikely to encounter.
For examples on how severe a beast-trait should be, look to the documentation supplied in similar beast-trait levels (sub-human or monstrous) using (+listinfo beast-traits) and (+explain <beast-trait name>).
Example SubHuman Beast-Trait (Bane) +jnote
Llewellyn will fear frenzy if he is presented with or is in the presence of a wooden stake.
It is possible to gain new Beast-Traits during the course of role play (+news systems/beast traits). When this occurs it is important that you add an appropriate +jnote if/when prompted.