It is your responsibility to keep your baby safe. Use common sense and double-check your knots.

Start by tying the waist straps around your waist with the Napsack hanging down, lining facing out. Tie a firm square knot and check your knots often	Bring baby up to your waist.	Older babies straddle your waist (newborns can "froggy" their legs up in fetal position.	Bring the body of the carrier up and toss one strap....
...and then the other strap over your shoulders.	Grab the straps behind your back and cross.	Bring the straps around to your front.	The lower you aim the X, the more comfortable you should be.
Tie a firm double knot. Older babies can have the knot tied right under their seat.	For a newborn, you can tie the knot higher -- against their back -- for extra support and to provide a "guard rail" across the open sides of the carrier.