thats soo simple
open your whatsapp like this and go to options bar like this
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select an option of "new group" like this
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now select your contacts and selected contacts will be shown as above.
now click on green arrow like this to go to next page or new options
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now enter name of group like i enter "friends" and click on green tick symbol
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now your new group will be shown on home page like this
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you can open group chat and write it down like this
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