My most time consuming one is- over felting everything I send out :) - it could take forever, since I want to make sure everything is firm and strong and movable parts remain firm and strong (reasonably, ofcourse).
My favorite part is wrapping- choosing tissue paper and ribbon colors and sticker design :D
Hardest part is getting my shop-address (online) stamp correctly on my shop card It wants to be smudgy :P)
and the silliest part is being overly tape-friendly over the bubble envelope :D
* I bought a box of envelopes few months ago, thinking it`ll last me a life-time and I`m almost out- THAT is really surprising me (and making me all giggly and happy and excited :D)