Here are my calumniated shipping tips from 20+ years of shipping delicate small to large items via any carrier.
never use a logo'ed label or a recognizable company name use yours but make it J.S. Smith
hand right you sables
use new boxes only
remember most carriers require proper packing read their TOS IE most items have to have a minimum of 3" of cushioning all around the object.
pack the contents so they make no noise when violent dropped or shook animals play with noisy things it make them curious if it is silent they go on to the next
do not use to much tape IE seams and opening and maybe one supporting wrap
insure the item for full value and packing costs
signature confrontation always
USPS to Canada and England it save the receivers so much red tape and fees
never lie on a customs form use repetitive technical terms to describe the contents IE sporting goods, two wheel transportation components, wire spokes, hubs, rims, assembled racing wheel components. ( a set of wheels) believe it or not they are trained to understand this better then just putting down bicycle wheels for racing
if in doubt be friendly ask a silly question of the counter person preference with your inexperience and knowledge that the question my be silly