The buckle is a magnetic clasp where the right side sits on top of the left.
There are 2 sets of straps, a lower for the waist, an upper for the hips.
The lower wants to sit at the top of your bottom & that’s the one to tighten first. Once you’ve set this you shouldn’t have to adjust very often.
The upper sits over the hips, tighten this second. You’ll find you adjust this one more, you’ll want to tighten when there’s more weight.
Lastly it’s best to settle the bag by pulling the buckle down so it's sits under rather than on the belly.

The bag itself is designed to be run tight. which means having it as compressed at possible, this stops it flopping about. The zig zag bungee does this laterally and a top strap to pull it in vertically.
There are 2 stoppers on the bungee so you can keep the bottom tucked until you need the space, & you can pull it all in if you’ve very little in there.
The top strap has another magnetic clasp and can be tightened, this is always best done up and tight so to stop your HipPac having a saggy bottom.
All the Velcro is RipFast, which means it sticks to itself! This gives you nearly 3x the adjustability of normal Velcro, plus you can fold any excess on the straps back upon themselves for less flappage.
When packing a gentle suggestion is to put heavier stuff at the bottom, this makes for a more comfortable wear.
HipPac is unpadded, this is to ensure the wrap around the waist is ergonomic and secure plus it saves weight. Therefore you might want to put a softer item in on the back side so nothing digs in too much.