In order to post pictures you will have to upload your picture to a photo hosting site similar to this one
http://postimage.org/
Select the image from your gallery, and have the website convert it into Forum Format. The site shown above will even automatically include the "IMG" tag so the forum will recognize it as a picture, so all you need to do is copy and paste!
If you are having trouble with picture uploading, I believe there is a topic about it on the main Nissan page of this Forum.
Welcome to the forum! Good Luck with your repairs!