There is a stereotype that all men are driven wild by lingerie. They love red, pink, and black, satin and lace. They love little school girl outfits and tiny Santa skirts during the holidays. Not all men are like this. Some are, yes, and some aren't. Outfits and lingerie can be a great way to set the tone of a session or to add a little bit of spice. If you're doing any role playing, it can definitely help. It also doesn't have to be a huge investment. Playing the stern school marm? Put your hair in a bun with a pencil and bring a ruler. That's what, three bucks for the pencil and the ruler? Playing the cheerleader? Get some knee-high socks and wear a crop top (which you can make with a white tee shirt and a pair of scissors). You may choose to go all out in your outfits, and that's fine, but if you're broke or lazy, you can also just suggest it. You and your partner are already using your imagination when creating a scenario. You can extend that imagination a little further into the outfits, too.
But what about standard lingerie? My boyfriend before X loved it. I'd get satin babydolls for him and he just went wild. X doesn't give a hoot about slips and lace. Like, at all. Does nothing for him. He likes me naked. But if I'm going to dress up, he likes black, fishnet, and leather. (classic sub). So I have a box of neglected lingerie. If I meet him naked in bed, he likes that the best. When you're learning what a partner wants, feel free to just ask what they like! If your partner is shy or not very creative, give him options. Say "Would you rather see me in a black corset or a red teddy?" "Which do you like better, satin or leather?" Help guide him to a place of dress-up. Just make sure that whatever you propose for your partner's options is something you're actually willing to wear. For example, I will never wear a school girl outfit because I was a Catholic school girl for ten years and I just don't get it. I mean, if X pleaded, I'd consider it, but I don't find it sexy in the slightest. (Fortunately, neither does he.)
But there's another side to this, a side which deserves recognition. When we put on outfits of any kind, we change our behavior in subtle ways. That's part of why Halloween is so popular - we like to dress up and put on personas. It's also why we have different dress codes for work and church versus casual clothes. We act more professional when we're wearing more professional clothes. It's true. A study was once done in which three groups of people took an intelligence test. These groups of people were alike in all ways except that one group wore jeans and tee shirts, one group wore artists' smocks, and one group wore doctors' lab coats. The "doctors" scored way higher on the intelligence test. We act differently depending on what we're wearing.
The fact is that while X doesn't find lace and satin sexy, I DO. And my opinion matters, too. It helps me get in the mood when I dress up a little bit for him. Sometimes that just means wearing matching lacy undies under my jeans and sweaters; when I take off the sweater, I know I look good and that matters to me. So if there's something you want to wear because it makes you feel sexy, be it a catsuit, knee high boots, or a plumber's overalls, it's okay to wear it to satisfy your own needs. Pay attention to your needs. We all want to satisfy our partners, but we also need to make ourselves satisfied, and that starts with getting in the right mood. That starts with feeling sexy. And that can mean sexy clothes.
Also, talk to your partner about what "casual" (not lingerie or role play outfits) clothes your partner likes. X likes me in casual dresses, but he also just loves jeans and tee shirts (seriously, how lucky am I?) That being said, he also appreciates a knee-high leather boot. I'm not willing to wear a corset on a day-to-day basis, but I am willing to change up my footwear for him, so just for him, I just got a new pair of pleather boots. We're going out for dinner on Friday and I fully intend to wear them for him. They hint that I'm a sexual person to my lover without screaming to the world "WE HAVE INTERCOURSE."
You can also find out what scents or hairstyles your partner likes. This can backfire though. For example, X loves bangs, the kind that cut straight across the forehead. Think Mia from Pulp Fiction. I have curly hair; there is no way my hair would ever do that. So I just have to accept that I can never pull off that look for him. (Fortunately, he also loves brunettes and I have very dark brown hair, so I win on that front.)
Just don't forget in all your exploring the world of dress-up that it's also important to do and wear what makes you feel sexy. Your ideas matter too. I have a tattoo on my foot and I feel incredibly sexy when I show it. Does anyone really pay that much attention to my feet? Probably not. But I notice it and that's enough for me. Find hairstyles or scents that make you feel sexy. Paint your nails bright red. Or black. Or whatever color you like. Try your hair in different styles - even parting it on the other side can make a difference. Play! Have fun! Experiment! Most of all, be you. Remember, that's who your partner finds sexy above all else: you. So be you.