When purchasing a backpack, you should consider how much you need to carry, what features you want it to have, and a key component is the fit. In order to have optimal comfort while hiking - be sure to purchase a pack that properly fits your torso and sits on your hips.
Start packing your daypack with putting extra layers on the bottom of your bag. These should be the layers that you pack as a precaution in case the weather turns. Not an extra hat you may want easy access to.
Pack your heavier items in the middle to bottom of your bag, and have them situated so they are pushed up against the back of the pack against your spine. It sounds uncomfortable, but actually will give your back more stability while carrying these heavier items. These items like camping stoves, emergency equipment for overnights etc.
At the top of my pack, I like to stack your lighter, easy access gear/food. I typically do extra socks, rain coat, heavy gloves and sandwich here. As well as my microspikes, first aid kit, and lighter emergency equipment in case I need to grab it quickly!
In your top pockets this should hold easy access snacks and valuables. I put my snacks, sunglasses, sunscreen, headlamps and anything I may want to grab or easily pack away. Little items like this are great in a pouch or pocket in your bag, so you don’t have to sift through your entire pack to find them!
If you have side pockets on the waist strap - I like to stock these with easy grab snacks, chapstick and tissues. Easy convenience = a more efficient hike with less stopping and digging through your bag
Trekking poles, snowshoes, ice ace should be arranged to evenly distribute weight on the pack. If your pack allows, you can attach one snowshoe on either side of the pack, or attach to the front center of the pack.
Be sure that the straps are adjusted properly, and that the pack rests firmly on top of your hips, adjust the shoulder straps so the backpack is high on your back, and chest strap is tight so that the bag doesn’t sway side to side.