[Nook HD, HD+ General] fljoe:
The instructions in the http://xdaforums.com/showthread.php?t=2062613 thread is as simple as it gets, anyway I am simplyfying if further. I am assuming you have the Nook HD+ 9inch tablet

1) Make a folder called Nook_Mod on your PC and download 2 of the files attached at the bottom of the post http://xdaforums.com/showthread.php?t=2062613. The files you need are:

i. NookHDplus-bootable-CWM-6023-for-emmc-stock-4GB-rev3-(02.17.13).zip

ii. NookHD-HDplus-Extras-rev3-(05.06.13).zip

2) Using WinRar or WinZip extract NookHDplus-bootable-CWM-6023-for-emmc-stock-4GB-rev3-(02.17.13).zip file. After extraction you should see a file called NookHDplus-bootable-CWM-6023-for-emmc-stock-4GB-rev3.img

3) Now download a program called Win32DiskImager from http://sourceforge.net/projects/win32diskimager/. This program is used to write the image file in step 2 to a microSD card. The download is in zip format, so you will need to unzip the file.

4) Get a 4GB microSD card preferably SanDisk Class 4 and insert it into the card reader slot of your PC. Once the card is recognized by your PC, note the drive letter for the card (ie E:\ or F:\ etc)

5) Click on the Win32DiskImager program. A box pops up and here make sure you select the correct drive to write to under the Device heading (ie. the drive associated with your microSD card). Click on the Folder icon in the box, right next to Device and select the NookHDplus-bootable-CWM-6023-for-emmc-stock-4GB-rev3.img file and then click on the "Write" button. It will take approximately 15 to 20 minutes to write the image to the microSD card.

6) After the image is written, exit out of the Win32DiskImager program. Remove the microSD card from your computer.

7) Re-insert the microSD card in your computer. Your card contents should look like the image I have attached to this post.

8) Now copy the NookHD-HDplus-Extras-rev3-(05.06.13).zip file to the root of the microSD card

9) Ensure your nook HD+ is charged completely and turn it OFF completely.

10) Insert the microSD card into the slot on your Nook HD+

11) Power ON your Nook HD+

12) You will soon see the Clockwork Mod (CWM) logo appear and your device will boot into CWM

13) Use the Vol+ and Vol- keys on the side of the Nook to navigate the cursor and highlight "backup and restore"

14) Press the "n" buttom on the bottom of the Nook HD to activate the selection which is Backup to backup your device. This will take a while.

15) Now press the "Power" button to go back to the Main menu and now choose "Install zip from SD"

16) Navigate to the NookHD-HDplus-Extras-rev3-(05.06.13).zip file you had copied to the microSD card. Select this file and click on the "n" button to flash this file and select install

17) After the file has been installed, you can remove the microSD card from the Nook HD and keep it somewhere safe. You might need to use this card again if you want to restore your Nook HD.

18) Now navigate to the reboot menu line and click on reboot and your Nook HD+ should boot back into the stock ROM.

Now you should be able to sideload any apps.

Please thank leapinlar as it is due to his efforts that this has been made possible. Also I am just re-hashing instructions that was in his thread, so all credits should go to him :)

Good Luck!