HIKING BOOTS are a must. The footwear needs to be sturdy and durable. Break in your boots before wearing them on the trip. Walk in them for at least several weeks, wear them to school or out for your training regimen activities. Buy boots in the afternoon after your feet have expanded to get a great fit. Wear the socks you will be using for the trip.

SOCKS
Two pairs of socks, one liner sock (lightweight polypropylene or nylon) and a heavy outer sock, are strongly recommended. Many of us prefer wool socks because even when wet, you feet remain warm. Socks should have heels. No tube socks; they fall down and seem to cause blisters.

Hiking expert & GORP contributor, Karen Berger, has written extensively about this topic and has the BEST tips on HikerWriter: https://hikerwriter.com/blisters-how-to-prevent-and-treat-them/ 
A summary is below.

Excerpted from GORP Magazine:

"After suffering my share of hobbled hikes, I decided to see if I could find a solution, I talked to boot reps, questioned my hiking buddies, and tried on enough boots to outfit a centipede. What I learned got me through all 2,158 miles of the Appalachian Trail without a single blister. Here’s the scoop: 

• Double check the boot fit. If you’re a beginning backpacker and you’re not used to the feel of hiking boots, wear them at home for a couple of days for several hours to be sure they are comfortable. Seek out a reputable store and an experienced salesperson to find the best fit. If you wear them at home and they don’t feel right, you can take them back to the store for exchange.
• Wear wicking socks. Polypropylene or nylon are fine - under a pair of wool and nylon blend outer socks. The wicking socks are less abrasive, plus they move moisture away from your feet. Never wear cotton socks- cotton absorbs moisture and practically guarantees blisters.
• Go easy on the mileage and keep your pack weight as low as possible.
• The absolutely number one most important rule of blister prevention: The second you feel the slightest hint of something rubbing in your shoe, STOP! Ignore your hiking partner’s pleas to just keep going. Find the pebble, grass-seed, clump of dirt, grain of sand, or wrinkle in the sock. If it’s a tight boot that’s causing trouble, rub the inside of your boot with the blunt rounded end of a Swiss army knife to try to stretch the leather or fabric.
• If you know you’ve got a vulnerable trouble spot, like the back of your heel, put a piece of moleskin on it before you start walking.
• Treat a hot spot with moleskin on the trail. If a blister has already started forming (it can happen in mere seconds), use a dressing called Second Skin (available from Spenco). This dressing was developed to treat burns – and after all, blisters are nothing more that friction burns. Whether you’re putting moleskin over a hot spot or adhesive tape over a Second Skin dressing, remember that tape adheres better to dry skin that wet skin – so use a bandana to dry your sweaty feet first."