OK, first the credentials: Started downhill skiing when I was around 8 years old (now in my early 60's), ski mostly expert runs in the Rockies, but am starting to leave the serious moguls to the younger set (knees just can't take it like they used to...) Also have gone cross-country skiing and snowshoeing regularly in the mountains. My take-- wear the right gear and you'll have fun; wear the wrong gear and you'll be cold, wet, and miserable.
Cross country and downhill skiing are two different sports. Cross country requires layers that wick away moisture. You'll be surprised at how fast you'll heat up once you start moving, even on a very cold day. BUT, you'll also lose that body heat very quickly once you stop, and, if your clothes are damp, you'll start getting seriously chilled. You'll need to peel off layers as you heat up and put on more layers when you stop. Start with a set (top and bottom) of polypropylene underwear (NEVER cotton!), lightweight/synthetic-knit/high-collar top, mid-layer of fleece--vest or zipped pullover, depending on temperature, bottoms only if seriously cold--and finish with a windproof jacket and pants. Hat, waterproof/wind resistant/insulated gloves (mitts if hands tend to get cold), and wool/poly socks (not too thick--your toes should have lots of wiggle room in your boots.)
Downhill skiing requires warm pants and jacket-- sitting on a chairlift for 20 minutes at -15C with a wind and snow blowing in your face can be a miserable experience if you don't have the right gear. After four decades, I've finally figured out what works best for me. I wear my polypropylene underwear, a 3/4 zip synthetic high-neck top (can unzip if I get warm), and my insulated ski jacket and pants. Downhill ski wear technology has evolved so that the gear is warm, waterproof, and not bulky. Hat, gloves, and ski socks complete the outfit.
Some more thoughts:
Go to a ski shop to check out the clothing and gear that is available. Try on jackets and pants, ask lots of questions, and check out brands and options. You don't have to buy your stuff at specialty ski shops if you are on a tight budget, but you'll have a much better idea about what to look for if you shop at discount or warehouse stores. The staff at ski shops are usually avid skiers and love to talk about gear.
My son has been a "boarder" for almost 20 years now and would cringe if he thought I was giving advice on snowboarding gear. If you decide to go that direction, you'd probably want to check out the gear with sales staff who are snowboarders. Snowboard pants and jackets are similar to downhill gear, but there are some important differences. For example, you definitely want a waterproof layer on your butt if you snowboard; skiers don't tend to sit around on the snow as much, so it's not such an issue with them.
When I buy a downhill jacket, I look for one that has sufficient pockets to hold my wallet, keys, kleenex, lip balm, etc. It also needs to have a high collar and a hood so that I pull it up if I'm stuck on a chairlift and the wind comes up. A good jacket also is long enough to cover my butt so my back doesn't come into contact with the cold metal on the chairlift. Pants need to fit comfortably in the waist and be the right length. They should also be easy to get off if you need to go to the bathroom. (My worst ski outfit was a very stylish, one-piece suit....) I also prefer zip-neck tops to turtlenecks because I can adjust them to suit the temperature. Gloves need to be flexible and have room in the fingertips so that my hands don't get cold. Socks also need to be warm, but light so that my toes have lots of room inside my ski boots.
If you are on a tight budget, you can pick up underwear, fleece, socks, hats, and gloves in discount or warehouse stores. Invest in a good jacket and pants. Check out higher end brands like North Face, Carbon, Bogner etc. but, once you know what to look for, you can save money by looking at some of the less expensive stuff by Columbia, REI, etc. You can sometimes get great deals on last season's gear or at a ski swap.
Consider buying your own boots, even if you rent skis and poles. Go to a specialty ski shop that has a boot fitter. He, or she, can help you find a good pair of beginner boots that are warm and comfortable. A well-fitted boot makes a big difference in your skiing and makes it much easier to learn how to ski safely and comfortably.
Long post, but I can't help but get excited when I hear that someone wants to take up my favorite sports. Go for it!
