DISCLAIMER
Here goes the cyanogenmod disclaimer. The same applies here.
"CyanogenMod members or anyone else on this website is not responsible for bricked devices, dead SD cards, thermonuclear war, or you getting fired because the alarm app failed. Please do some research if you have any concerns about features included in the products you find here before flashing it! YOU are choosing to make these modifications, and if you point the finger at us for messing up your device, we will laugh at you. Your warranty will be void if you tamper with any part of your device / software."
1. Turn on usb debugging from developer settings.
2. Install drivers like
this.
3. Download and install
this.
4. Open and click Root(Make sure you're connected to the internet).
And...you're done!
To unroot press the remove root button in the same application.
A1000F USERS PLEASE READ
Some A1000F users have reported that the device will turn off after rooting and won't start until you plug in the charging cable. After that it works fine. Refer to the comments below. If your device fails to start after rooting, please try
this.
Keep in mind Lenovo will have an absolute right to deny your warranty claim(you are of course free to try, they may not even notice) if you give them a rooted device. So make sure you unroot the device before taking it to the service center, unless the device is completely dead.
UPDATE
Lenovo has finally rolled out an update for A1000G that increases the internal storage to 1.5gb.