This is a short tutorial explaining how to use MyEtherWallet to get the same information and result you can get with the official interface on https://eos.io website.

For the rest of the tutorial, you will need the contract address and the ABI (visible under Contract Source tab). You can get those both by following the link posted here:

https://steemit.com/eos/@eosio/eos-io-temporarily-unavailable

Everything you do from now on begins with these steps:

1. Go to https://www.myetherwallet.com/#contracts
2. Add the contract address and ABI in the provided fields
3. Select the required function

Let's start with some light reading:

Get the current window number

Find out what the current window number is.
Function name: today
Returns: 0-index number. 0 is the first 5-day​ window

Get the number of tokens on sale today:

Function name: createOnDay
Parameter: window number
Returns: Total numbers of tokens on sale on the day in it’s smallest subdivision divide this by 10^18 to get the number of actual EOS

Example for day 0 returns: 200000000000000000000000000
To get number of actual EOS you will get: 200000000000000000000000000 / (10^18) = 200000000 (200,000,000)

Number of total ETH contributed on the day:

Function name: dailyTotals
Parameter: window number
Returns: total ETH contributed in the window in wei. Divide by 10^18 to get number in ETH

How much ETH did you send on the day:

Function name: userBuys
Parameters: window number, address
Returns: total ETH contributed by that address​ sin the window. Number returned is in WEI (divide by 10^18 to get ETH)

Using the numbers above you can calculate the following:
Effective price: dailyTotals / createOnDay
EOS you get: userBuys / Effective price

But I want to BUY BUY BUY!

Of course, ​the three most important operations you want to know about are:

1. Sending your ETH in
2. Claiming your EOS
3. Registering the EOS public key so you can claim then on EOS chains

The three are described on the MyEtherWallet page of the contract:

Let’s dissect this a bit:

Generate EOS key-pair

You need this to be able to claim the currency on all blockchains that will be launched on eos.io software who choose to use this distribution as they first block. You can use this tool to generate a pair (works in any browser): https://nadejde.github.io/eos-token-sale/
SAVE YOUR PRIVATE KEY! YOU CAN NOT RECOVER IT!

Register/Map your EOS key

After you have the key you can associate the address that has the EOS tokens to the new EOS key. On any chain that uses EOS.io you will be able to use the generated KEY to access currency.

Fund EOS Contract

This is how you send ETH in to get EOS. Straight forward!

Claim EOS Tokens

Because of the way this sale is built you do not get the EOS tokens right away. You only get them at the end of the window when the final price for that window has been settled. This is why you need to use the claim function when you actually want to take ownership of the EOS tokens. You can use this at the end of every day.