If you're not sure what category your Instructables fits in, have a look through and see where there's the closest match. The categories are guidelines, and are not meant to be rigid. Plus, if we get enough new Instructables of a certain type, we'll add another category.
You still need to add keywords to your Instructable, and within categories, these will be even more useful.
All the Instructables up until approximately a week ago, were categorized by me. If I put your Instructable in the wrong category, please accept my apologies and proceed to step 1 to re-categorize it.
Step 1: Put Your Instructable in a Different Category
Click the "publish" tab, and then click the "unpublish" button. This will take you to the publish page, where you can change or add your Instructable to categories with the pull-down menus. Next, hit the publish button. Unpublishing and re-publishing your Instructable does not affect its original publish date.