JailbreakMe has made the jailbreaking process as simple as ABC. Here is another guide to jailbreak iPad on iOS 3.2.1 using the latest JailbreakMe tool. In case you have iPhone 4, read the instruction here for jailbreaking; and for iPhone 3GS, head over to this post for howto guide.
Step 1: Download the latest iTunes 9.2.1 and backup your images, apps, vidoes contacta, calendars etc.
Step 2: Now update your iPad to latest iOS 3.2.1. This step is not necessary. You can also jailbreak your current firmware version using JailbreakMe.
Step 3: Using a reliabale internet connnection like WiFi or 3G, point the browser to this address http://jailbreakme.com
Step 4: “Slide to Jailbreak” to start the jailbreaking process.
Step 5: Wait till the required files are downloaded.
Step 6: When the files are downloaded, the jailbreak process will start. Don’t interrupt the iPhone at this point.
Step 7: Once the jailbreak process is completed, you will see the message “Cydia has been added to the Home Screen”.
Step 8: Close the browser and look for Cydia in the springboard. Enjoy your jailbroken iPad on iOS 3.2.1.