Screenshots below explains you better to setup sync your mobile contacts with google contacts. Follow the following steps.
Settings

Connectivity
Data Transfer

Sync

Options -> New sync profile

Start
Page 1 : Give any name in Profile name -> Next
Page 2 : Select Server version 1.2 -> Next
Page 3 : Select only Contacts in "Applications in sync", remove other checkmarks in that list. -> Next
Page 4 : Type "Contacts" in Contacts database field. -> Next

Page 5 : In Data bearer select Internet -> Next

Page 6 : In Host address give https://m.google.com/syncml. Note that 'https' is must. -> Next
Page 7 : Give "Google" in Server ID. Note that in Google , "G" must be uppercase.
Page 8 :Give your gmail ID in User name -> Next
Page 9 :Give your gmail password -> Next

Page 10 : Save this profile settings -> Yes

Thats all. Finally select "Options -> Synchronise"

Your contacts will be synchronized with Google Contacts