There are a couple steps to the application process. If you follow them you're more likely to get your application cleared through.
1. Gather the information together for your application. This means figuring out what you want to apply for, see that section.
2. Write a glance description. This is one of the requirements for any type of application character, so you should make sure to do one. See help description. A good glance description can be written in only a couple lines, but there are some things to consider. Try not to include clothing or items unless that's the type of stuff you would always have with you. Also, don't force opinions on people "the most beautiful woman you've ever seen" etc etc.
3. Write a character background/biography. This is perhaps the most important part of the application itself. This shows the Immortals that you've really thought through the character, explored their history and motivations, and know some of how you're going to play them. If your background isn't at least 500 words, forget it. It really is pretty easy to get the length up though. Here's some ideas to consider:
* Where were they born?
* What were their family like?
* What were some important things that happened when they were a child?
* Did they leave home? Why? Where did they go? Was anyone with them?
You should take care with this last one. There are many backgrounds that come through with the family having been killed/eaten by trollocs/whitecloaks/aes sedai/nobles/fish/etc. These are a dime a dozen, and won't impress anyone. Instead, perhaps you should consider showing that you can be innovative and original in your background writing.
4. Then it's time to actually write the application. The sections are:
First, your name, your email address, and a list of all characters you have played at TSoS
. Be as complete as possible. After this should come your glance description, then your background. The last things should be a description of what exactly it is you want (wolfkin/warder/sedai/noble/forsaken/blacksmith/ogier/aiel/etc.), why you should get it, why it will help the MUD, what you plan on doing with the character, and (be specific!) what you want them setup with for forms, skills, attributes, special items, etc. It is important to touch on pretty much each of these.
5. Once you have your application wrote up and sent off to email@example.com (there's a form on the website to do this for you, you should use that now) it's basically time to play the waiting game. You should make sure to alert the Immortals that you've sent an application in, but you should be very patient. It can take a while to get your application fully considered.
6. You should remind Luthien or whoever is handling the applications once a week/every few days that you've got an application in. Don't bug them, just send them a brief, polite tell inquiring about it, such as "Just touching base with you to remind you that I have an application pending." or something like that.
Some side notes:
There are certain types of characters that will have higher standards for the application than others. Some examples of this are: Wolfkin, Aiel, Ogier, Forsaken. The last two in-particular will require that the Immortals know a player fairly well and are certain of their abilities.
Also, there is an adendum to the application for Aiel: In addition to the above application process, you'll be required to write up a page (another 500 words at least) of essay about the type of aiel you want (society, clan, etc.) this should be detailed enough to let the Immortals know that you really have an idea of what it takes to be an Aiel since they are so complicated.