[Q] Rooting Chinese Android 4.0 dual sim phone

I'm a new member here and i have a china dual Sim phone, which is a replica of GS3 mini that i want to root

The phone details are:
Spreadtrum Phone
Android version: 4.0.3
Model: GT-I9300
Build number: MT6515M_C909_HT_EN_V04

Any idiot guide on how to root this phone please? im a rookie in rooting

Ta