It is really easy
1) Go to your versions folder.
2) DO NOT DELETE THE "1.6.2" FOLDER.
3) Create a new folder (ex: Hack1).
4) Put your .jar inside and rename it with the same name as the folder (ex here: Hack1).
5) Then you can copy the .json file from the "1.6.2" folder and put it in your new folder (here: Hack1).
6) Now, in your folder (ex: "Hack1") you will have "Hack1.jar" and Hack1.json".
7) Open "Hack1.json" (using NotePad or anything else) You will see that a the second line there is ""id": "1.6.2",". Just replace "1.6.2" with "Hack1".
8) So now, all the files have the same name and you replaced 1.6.2 with Hack1 in the .json file.
9) Open the minecraft launcher.
10) Click on "New Profile".
11) Choose any name.
12) In the section "Use Version" you just have to select the one you created.
13) Then save profile.
14) BOOM !
Hope I helped

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