There are multiple ways
to upload and add images and files to your Instructable.
The details below discuss the image library, but it applies in much the same way to the file library.
Each user has an image library with all of their uploaded images.
Each Instructable has its own image library with each image attached to that Instructable.
The 'This Instructable' image library makes collaborating with others easier because it gives each collaborator access to the images.
We have a new beta uploader that will allow you to select multiple files/images from your dialog box. Just click on the 'Try the new uploader' and use Ctrl + click to select more than one image.
You can upload images directly to you library here:http://www.instructables.com/upload
We have a beta Flickr upload tool available in your library or on the upload page under the 'flickr import' tab.http://www.instructables.com/upload
This allows you to import images from your Flickr account into your Instructables library.
You can upload images directly to a step on an Instructable, comment, or forum topic by browsing for the file under the "Upload" section directly under "attach images" and "attach files" tabs.