This is easily one of the most important steps of sending your application. A well ordered application can sometimes make all the difference. I'm not saying that simply packaging your application well will you get you an admit from your dream school, but it sure will help in increasing your probability of getting into a school you already had a good chance of getting into.
What is an application packet?So you have heard your seniors say, "I have to start sending my application packets soon", and you have always wondered what did that packet hold, afterall.
But, like, um, what goes into it?Lets make a list of things an application packet should hold. This list may vary according to the requirements of the schools you are applying at. This list may also vary according to the kind of person you are. If you like sending in extra papers, just to be sure that you have sent everything - to get some peaceful sleep at night, or if you do not like burdening the already overburdened and understaffed admission offices of your probable schools.
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First and foremost - A cover letter.
Acads Related:1. Transcripts
Sealed + Signed enevlope holding each set of attested transcripts.
2. Letters of Recommendation
Sealed + Signed Envelope holding each letter.
3. College Marksheets
Absolutely no need to include KT marksheets, if any.
Some may find sending marksheets to be redundant as you are sending the transcripts already.
4. Passing Certificates
The tiny white certificates you get after your FE & BE in Mumbai University. Don't worry if you haven't received the BE certificate yet.
Sealed + Signed enevlope holding each set of attested marksheets + passing certificates
5. Degree Certificate
Again, don't worry if you haven't yet received it.
Test Scores Related:6. GRE Scoresheet
7. TOEFL Scoresheet
If there is a lag in score reporting, this will make sure that the school knows about your testscores already
Work Experience Related8. A letter stating that you have been employed with the company, your duties and the duration of employment.
Finance Related:9. Form provided by school stating financial standing, if provided online.
10. Affidavit of Support.
11. Bank Statement stating financial standing.
DO send 9 and 10 if explicitly asked, else it is your choice to send or not.
I-20 Related.12. Copy of Passport
Yaay, so you got an admit from your dream school. But you are in a mess because they misspelt your name on the I-20. Don't let that happen. Let them know again what your full name is. Make sure you spell your name on the school forms exactly the same way as it is on your passport. And that the first and last names go into the right columns.
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[I shall be gradually uploading formats for some of the above documents when I have the time to]
Putting it all together:Each of the above documents go into their own white envelope. The small white envelopes I am speaking about are size 10 envelopes, each costing around Rupee 1.

On each envelope, make sure you write your NetId, or any kind of identification provided to you when you applied online. If you are stapling things together, make sure you hit hard on the staple pins after stapling, to eliminate sharp edges. You don't want your application to hurt the one evaluating it.
And in what do all these envelopes go?You might want to consider buying an expandable wallet to package your application in. An expandable wallet is also popularly known as a half harmonium folder. If you live in Bombay you can get these at Abdul Rehman Street, which is along Jumma Masjid's lane, opposite to Crawford Market. If you live in any other city, you might get it at a place which stocks office supplies.

This is what an expandable wallet looks like. They do come with their own glossy inserts on which you could neatly label what each part of the file contains. These inserts come free with the folder, but you might want to replace them with something you print out on hard cardpaper and cut to size. The reason I did not use the free inserts were:
1. They were too glossy, writing with a ballpen smudged them.
2. They did not fit correctly into the tiny plastic slot. They were smaller than the slot and kept moving down reducing their visibility.
Each wallet might cost you Rs 40-80 depending upon their quality. I bought my yellow and white pretty wallets for Rs 50 each. If you are applying to 10 schools, total cost goes up to Rs 400. If you have gone - what, Rs 400 more, I am broke! - relax. It is just a fraction of your application expenses.
If you think your application will look better and be organised better in an expanding wallet, make that trip to town to buy them. Buy atleast 10 at a time so that you don't have to go back when its peak application season and you are crushed for time. It will also save you some money to buy in bulk.
Final PackingIf you consider the expandable wallet option, or some other innovative option, make sure it all goes into a Manila Envlope. A manila envelope is the light green envelope with a jute interior.
Write the address on the envelope very clearly with a black marker. DOn't forget to include the return address.
Which courier service should I use?This depends upon how early or late your application is. Make sure your application reaches before the deadline, and then decide which service to use. Popular courier services include:
1. DHL [Rs 937 for a packet under 500gm]
2. Fedex [please send in rates if you know for a packet weighing below 500gm]
3. UPS [please send in rates if you know for a packet weighing below 500gm]
4. TNT [Edulix has a deal with them, offering the lowest prices. Log on to
Edulix to find more]
5. Apna EMS. Cheapest and supposedly quite reliable.
6. US Returning Aunty
7. Couriered in bulk to US based aunty [provided she's not a lazy woman who won't send your packets at all]
Some of these courier services have expensive overnight express options, which you might want to use if you are really late.
I would not ask you trust your applications with 6 and 7. Be in control, always.
Things to buy & Packaging Expenses
This assuming you are applying at 12 schools.
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I would advise you to apply early. Especially at schools which have rolling admission - they hand out admits and rejects as the applications come in, you have a better chance of getting through with an early application.
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If you do have any relevant questions, leave behind a comment and I can add it into the post for future readers.