Just make sure you are actually getting a workout there. I go spinning now and then, usually when the weather is nasty enough to make me not want to be outside. There are a lot of different types of people there. There will be the people who look like they are really working out, but then if you pay attention you'll notice they never really crank up the tension. There are those that crank up the tension too much, and end up leaving or not doing much work half-way through the class.

better than the bored, monotone, going through the motions types.

I hate those saddles too. But you can bring your own quite easily. I was doing it last winter, but only for the longer (90 minute) classes.

I had a saddle attached to a 7/8" round post seat clamp just like the ones on the spin bikes (pictured). I just came in with that and the proper size wrench, and had the crappy, wide saddle off and mine on in about 30 seconds.

Wear your normal cycling jersey and shorts- Shoes take your trainers first time. Extras- Water Bottle and a towel- You will sweat a lot. Main advice is to realise that you may- MAY- not be as fit as others- so don't try and stay with them. If it hurts first time out- It is not the class too hard- It is you not being fit enough or you putting too much into it.

It takes me a couple of lessons to get into the routine of Spinning again after a summer of normal riding so take it steady at first. And don't invite any of the other class members out for a ride- They probably do not even own a bike.

true, both are pretty annoying, when I did a spinning class it was funny as hell the teacher was a chinese lady with a really thick accent and she talked SUPER fast, to the point it was funny it sounded like she was rapping.

Saddle up next to the attractive woman of your choice, introduce yourself and then see if she continues the conversation.

Good idea. Bring wife to spin class... <noted>

<noted> Someone's wife must be in the same room, reading over their shoulder.

I started doing spin classes this fall, so as a relative n00b, I can give a few pointers for what they're worth:
- cycling shorts, for sure
- i just wear a wicking (you sweat a LOT) t-shirt, not a jersey... although you certainly could wear a jersey without anyone caring.
- SPDs...I put spd cleats on my road shoes (riding the 'cross bike outdoors this time of year anyway...) Most bikes have pedals with SPD on one side, straps on the other
- water - I take 2 bottles, and usually drain them both in 45 mins (you sweat a lot!)
- towel - to stop from forming puddles (or at least reduce the size of the puddles) - did I mention you sweat a lot when riding indoors???
- HRM - I did the first few classes without mine (battery was dead) and thought I was working pretty hard (based mostly on sweat production I think) but when I got my HRM back, realized I was never getting my heart rate about about 80%...it's deceiving. Now that I am taking the HRM, I feel I'm getting a much better workout
- Agreed that the fat/soft saddles suck.. I almost feel like requesting they put decent saddles on at least a couple of bikes (I go to classes at a local bike shop that I have a good relationship with...)
- ignore the instructor when they tell you to move your upper body around... keep your outdoor riding form rather than starting bad habits during the winter!

ennis shoes or Road Shoes? both, see if they have your clips
Bring pedals or not? no
Cycling shorts or gym shorts? either, wear shorts until class starts over unless you want attention
iPod or nothing? they provide the music
water bottle or nothing? water bottle! youll sweat your arse off, theres no wind resistance taking your sweat away
Anything else? a towl, you will sweat everywhere. also, bring a spare change of clothes, youll freeze when you walk out the door.

holla nasti nati, where i was born and raised! who dey!

My two cents:

Basic Wkout shirt NOT Cycling. - I would simply wear a wicking jersey and I use sleeveless as it is so hot.
I save Cycling jerseys for cycling as I figure easier to wash / dry others cheap wk out ones.

Basic wk out shorts with like leggings /under armor underneath - Seat is padded - no need for cycling shorts. This way you can go wk out after, and easier to wash/dry etc.

Water-or gatorade - you will need it.

Mid size towel - you will sweat alot.

Wipes - if gym does not have them - not a bad idea to wipe handlebars for germs/winter.

Extra shirt - I sweat alot so bring extra shirt for after.

MTB shoes preferred - this way you can walk easier and not slip when stretching etc.

Try different instructors to see who you like.

Ignore instructor if they make you do some silly wk out on bike or try to make you stand too long.
Create your own intervals / zones / recovery if they are clueless.

HRM - till you figure out your intensities etc.

Try out several spin instructors. Some instructors are more bicycle oriented. You can get an excellent workout. Pick you instructor carefully.

Some suggestions to spin class instructors from an old grouch:

Don't tell me to smile during an out-of saddle sprint
Don't expect me to whoop and holler
Give cues on how long each sprint, climb etc. will last
Make sure the bikes are well maintained (loose crank arms and sudden loss/increase of resistance are regular problems)

Otherwise, it's a great and enjoyable workout, especially when winter weather keeps you off the bike. As mentioned earlier, a lot depends on the instructor. You can get more variety by going to more than one.

Exactly what I was about to post.

I just wear my running shoes and strap in tight. I don't have time/room in my bag to carry my road shoes, pedals, and a wrench around all day and they only have two SPD pedals.... on two different bikes.... dumb.
I normally don't bring a water bottle and just drink a lot of water on days I spin. If I'm pushing too hard, I'll get off and take a break just for long enough to get to the water fountain and back.
The towel is probably the most important thing because eventually your shirt is going to be too wet to wipe your face onto your shoulder.

In your gyms do the spinning bikes have really relaxed angles? I'm almost 6'2", but I find myself sliding the saddle almost all the way forward just to get a feeling somewhat like my road bike.

if you do it right, you could get a great work out AND a number all in one night. it is very possible. just make sure there are other classes available if she gets annoying or you change your mind. that would be an awkward spin class.