People about Cosplay...
Putting aside for the moment that the tone of the question doesn’t imply the most open of minds, cosplay is – simply – acting. Do you consider Mel Gibson, Ken Branagh, David Tennant, Cumberbatch, et. al. immature for wanting to dress up and act as Hamlet? Cosplay is a similar – if not identical – mindset: people, inspired by characters, possessing the right combination of talent, bravery and self-awareness, performing as said character for an audience. Whether it’s a convention stage or a Broadway stage makes no difference. The person who portrays Deadpool or Master Chief is very much spiritual kin to the person who plays King Lear or Hamlet. It’s wrong to praise one and denigrate the other based on the source of their inspiration, for to declare which works are “great” and which are not is subjective or worse. Still, even if most consider it blasphemy to compare Marvel to Shakespeare, the motivation to portray characters from either realm is identical and the healthy mindset WON’T criticize this, realizing that whatever it doesn’t “get” is not automatically inferior or invalid.
PS: Ironically you will find, if you but ask, that most cosplayers as children were very successful Trick or Treaters, as Halloween is quite often the “bug” that bites them for their subsequent motivation.
Costuming has been around a long time: we find artifacts from tens of thousands of years ago where they were used to portray a being or spirit. Often those who played the parts in costume were held in high regard.
A little time with kids or a parade group reminds us all how much fun people have – let alone when there is a formal play being staged. Costuming is fun; it’s fun for people to pretend, but it should be understood by all that it’s to be pretend. Problems come when the “role” gets mixed up with one’s being; the role defines the person instead of the person defining the role.
As Jack Nicholson famously said to Michael Keaton as they were suiting up for their roles in Batman (1989): “Time to let the costumes do the acting.”
When the role is more than the person, that causes psych problems.
Pick your favorite character, or one you would have the most interest in creating, and start looking for items that can be turned into props. Go to the thrift stores and find clothing that can be altered, or may even work as it. Figure out how to do an ‘adaptation’ of a character – for instance, I have a Rarity (My Little Pony) costume that is a purple skirt, purple and white blouse, large white hat and purple wig. I have either white or purple heels to go with it, but I forget which. Everything except the wig was repurposed out of my own closet.
If you haven’t done any costuming at all before, pick a character that usually wears ‘street clothes’. There are also a ton of eBay sellers out there that offer custom made cosplays, but you have to be careful and read reviews about their sizing – a lot of them tend to run small. I’ve also bought stand alone pieces like corsets, boots, purses, etc., from eBay and Etsy. This one store on eBay sold cheap corsets for ten bucks each – they didn’t stand up to long term use, but they did work for about a year of conventions, each, and held up pretty good for the per-wear price. Anything you buy from a China eBay seller, plan to give it a month lead time. I usually get wigs and whatnot within 2-3 weeks, but the sellers usually say to allow for 30 days. And there are a lot of good inexpensive wigs on eBay too!
If you don’t sew, there are a lot of ways to get started, even if you aren’t crafty at all! those are skills you can pick up later on if you have a desire to.