To activate your iPhone 4 without a sims card, (Also known as Hacktivate), you need to make sure you download the latest version of RedsnOw and the 6.0 IPSW that matches your iPhone. You can find that download and many others at iDownLoadBlog. When you have completed those downloads, walk through the following steps:

  • Right click on RedsnOw, choose Properties.
  • Click on “Compatibility” and set the Operating System of your iPhone into the options.
  • Click “OK”.
  • Relaunch RedsnOw.
  • Choose Extras.
  • Select IPSW (The one you all ready downloaded).
  • Click OK.
  • Click on Jailbreak and wait for that process to complete.
  • Install Cydia (Look for icon on Home screen after downloading RedsnOw).
  • Click “Next”.
  • Hold iPhone power button down for two seconds to get into DFU mode.
  • Continue holding button for 8 more seconds, while also holding the home button down at the same time.
  • Continue holding down the home button, but release the power button, hold for about 14 seconds
  • As you are holding down the home button, you will see the RedsnOw pineapple logo and then you will see the Apple Logo.
  • When you see the Apple Logo it means that the hacktivation is complete.

Resource: iPho9