I like LRPing in a group. If you have a group of people you can agree a common look. This helps with establishing an identity. You don’t need a personal identity if people can work out your place from the kit you’re wearing.
You can use it to add resonance. When we played tree worshipping cultists we all wore generic kit underneath and hoods and robes over the top. The look hinted slightly at a religious order which was mirrored by the way we spoke about our selves. The bulking up and furs often worn by beastkinmakes the people wearing it more likely to lounge around on a hot day, and also improves their ability to both hide and loom, which are important ways of separating your behaviour from that of other people.
In the star wars films they used very different clothing styles for the imperials and the rebels. If they are wearing black and have a mandarin collar then they are imperial. The clothes were very fitted, military and ordered. The rebels tended to have layers, v necks and clothing that was loose but belted. We used the same styles through Alone (although this rarely came up). It does mean that if you use those styles anywhere then people will see them in the same way.
I like things to have a coherent look. Anything that looks good does, and things with a coherent look invariably look better. One poly cotton tabard invariable looks quite cheap - a group of them in the same colours look like something meaningful.
For fantasy LRP I would expect anyone who has been to a couple of events to have IC trousers (appropriately coloured, not jeans or combats) and an ic top (not a t-shirt or something with a modern cut). I have advantage that I generally know what look I am going for and have both money and time to make the items I am after. I’m also of the opinion that in the same way that you couldn’t play cricket without the appropriate gear (the less gear you have the less like cricket it is and if you take this too far we end up arguing about whether throwing a turnip at a spade is cricket), you can’t LRP without the appropriate costume.
LRP is a luxury hobby. You can get appropriate kit for most things for less than the cost of one event.
Most people apply resonance automatically. If they’re playing the groups religious leader then their costume will be taken from their view of what a religious leader will look like. There are numerous interpretations of the phrase ‘Space Cowboys’ but if you use it currently most people will start to look to firefly for inspiration and you’ll get themes that come from there.
If you have an established world you’ll probably want players to be able to identify things from within that world. For example, if you have a particular military unit then you may want players to be able to identify that people are from that particular military unit. Military uniforms create a military look and badges, insignia and hats can be used to tie a group of soldiers into something the players recognise. We’re often tempted to create a set of police-ish uniforms, a set of paramedic gear and similar. We already have a decent set of military gear. A lot of people have a set of military gear, as it’s cheap and easy to buy. A lot of modern or post apocalyptic games are flooded with it when there’s a lot of alternatives that could be used.
We also consider whether it’s a one off event or a series of events. One offs require players to buy in very quickly. They only have 30-40 hours of game time and spending a lot of that working out the setting can really limit things. If it’s a series of events then you have more time to play with and can spend more time establishing something as a setting. You need to work out how much your players will happily read and at what point you’re being so constraining that you’re not leaving them room to make the world their own.
Finally, on another topic, we’re planning on running Jurassic LRP on 25th-27th September 2015.The facebook group is here. Let us know if it’s something you’re interested in. More details after Christmas.