The Evo 4G was rooted some days ago, and we finally have instructions. And it couldn't be easier. If you're new to this, we suggest you read through the thread at XDA Developers. And then read through it again. And after you think you don't have any more questions, read through it one more time. (Note: THIS WILL WIPE YOUR PHONE.) For the advanced, it's this simple:
1. Download this file (PC36IMG.zip). Move it to the root (as in top level) of the Evo's storage card.
2. Turn the phone off. Once it is, hold down the volume button and the power button until you get a white screen and some text. You're now in the bootloader. It should automatically start checking the PC36IMG.zip file you put on the card.
3. Once it's done, it'll list all the images on the card and ask if you want to flash. (This is your last chance to back out.) Say yes, and we're on our way. It'll look like this as it's going:
4. After it's done, it'll ask if you want to reboot. Surely.
That's it. You have a rooted ROM. You'll want to rename (or delete) the PC36IMG.zip image file that you put on the card, so that next time you enter the bootloader it won't try to automatically update again. You can do that by plugging in the phone, choosing "HTC Sync" and going to your favorite command line prompt and typing:
adb shell mv /sdcard/PC36IMG.zip /sdcard/root-PC36IMG.zip
Leave the phone plugged in if you want to go on to the next section and load the custom recovery. (After the break, for cleanliness.) Otherwise, you're done.