Here is how it works:

first you go on this site:

https://ssl.dlsite.com/maniax/regist/user

Then scroll down to the field "ログインID ". Its the onl field on this site. There you put in your nickname you like to choose. there are two optionbuttons over this field. Click the left one with "同意する", this meens "I agree".

And then the left button on the bottom to confirm.

Then you come to the registration form. this is the order of Fields:

お名前 : Name

お名前フリガナ : Name in Furigana

(you can just choose the examples below the fields: 山田太郎 and ヤマダタロウ )

電話番号 : Phonenumber
(just take the example and change some numbers)

生年月日 : Birthday

メールアドレス : Mailadress
(some mailadresses wont work, like hotmail.)

メールアドレス（確認) : repeat mailadress

ダウンロード制限金額(一ヶ月間) : Limit for downloads per month

・メールマガジン(無料) : Newsletter

お名前(ローマ字) : Name on Creditcard

カード番号 : Creditcard number

クレジットカード有効期限: Credit card expiration date

ログインパスワード : Login pasword

ログインパスワード（確認) repeat password.


Now you can always log in and just need to buy mangas