Why take a lesson at all?
If you have never snowboarded before, you should really take a lesson. Snowboarding isn't as intuitive as it looks. Just making your first turn and stopping will require you to work muscles you probably haven't used before.
More importantly, if you don't learn how to ride properly you can easily injure yourself. Many first-time snowboarders are rewarded with a broken wrist if they aren't careful.
How should I dress?
Unlike skiers, snowboarders spend a lot of time in the snow by design (more on that later). Two items of clothing you'll definitely want are a pair of ski pants and a pair of gloves.
For pants you are going to want a comfortable pair of ski or snowboarding pants. Whats the difference? Well, snowboarding pants are designed specifically for snowboarding by being looser so you can get up out of the snow easier. More importantly, they'll keep the snow off of you. They also come in really cool designs and colors, especially if you are a fifteen year old boy.
By the way that pocket on the one leg near your boot is to keep anything you might want to easily access while sitting in the snow with your friends.
Gloves are important because you'll be picking yourself out of the snow a lot. If you wear knit or wool gloves, they'll be packed with snow and soaking wet before the lesson is halfway through.
Both items should be water-proof or at least water resistant. This is important because you'll want to keep dry.
Beyond that, dress in layers. Long--underwear padded with sweatpants and a hoodie work great. Add your pants on the outside and you're off to the races.
A good hat is always nice and you'll want goggles or sunglasses depending on the weather.
One great piece of apparel that most newbies don't know about is the neck-gator. It's a tube of fleece that goes around your neck. You can pull it up to cover your face and it won't freeze like a neckerchief. Plus, you can wash it later. After a day of collecting snot, sweat, and saliva you'll want to clean it.
Should I wear a helmet?
A very smart person once told me that wrists and arms heal, but brains don't. So it's not a bad idea. You probably won't need on in a beginner lesson, but once you start hitting the slopes (literally) you'll probably want one.
One thing- make sure it fits! A helmet that doesn't properly cover your temples is useless.
What type of lesson should I ask for?
First, make it clear that you want a snowboard lesson. They sell ski lessons too and you don't want any confusion. Make sure you tell them what ability level you are (beginner, intermediate, or advanced). Many places offer special packages for first-time beginners that include a lift ticket, lesson and equipment rentals.
You can also choose between a group lesson or a private lesson. In a group lesson, you and up to fifteen people work with a single instructor in a structured environment. A private lesson is just you and an instructor. Either way, they'll teach you the basics. Most lessons last about an hour, but many hills offer longer programs.
Should I ask for a specific instructor?
When you buy a group lesson, an instructor will be assigned to you. Chances are they won't offer you any choice.
If you purchase a private lesson, you can usually choose who you want. You can ask for a specific instructor if you know one. Most people just state a preference based upon gender or age because they may feel more comfortable with a certain type of person.
Better yet, you should ask for a certified instructor. The American Association of Snowboard Instructors offers instructors a certification program that evaluates their teaching and riding abilities. Most mountains will have several that have passed their Level One certification. This means they have completed a two day course that sharpens their riding and improves their teaching. You can't really go wrong with a person like this. They are committed to teaching and really enjoy what they do.
If you can find a mountain with a Level Two or higher certified instructor, you can almost guarantee success. Instructors with this level of training are top-notch. Their riding is superb and they can teach like masters.
Should I rent equipment?
Certainly if you don't own anything. Most resorts will have equipment to rent. You'll need boots and a board. Just tell them your shoe size and the rental shop will take it from there.
The boots are like over-sized snow boots and should fit snugly. Make sure your toes aren't cramped. Don't tuck in your pants either. You want the boot to fit smoothly around your calf.
There's usually an inner liner to the boot. Many of these have their own lacing system, so don't forget to tie that up first. Then lace or strap the outer boot so it's tight.
Am I goofy?
Well you are snowboarding! What this refers to is which foot goes down the hill first. In snowboarding, like skateboarding or surfing, you ride sideways. So you need to know which is your dominant foot. Usually it's opposite your handiness. So if you are right-handed you ride with your left foot forward, or "regular". If you are left handed, you right foot goes down the hill first- hence you are "goofy". Don't worry, it's an old skate-boarding term and has nothing to do with your personality.