Action Details
Requirements and how-to articles for Instagram's action:

Upload or take new photo via your mobile device.

You need this to get it done:

iOS, Android or Windows Mobile Device
In order to upload photos onto Instagram, you need to do so using a mobile device via the official Instagram app.
Photo(s) to be posted. Either uploaded from the phone's library/gallery or taken in the moment.
Caption (optional)
A caption can be added to the image you uploaded (maximum of 2,200 characters.) Hashtags can be added by adding a word prefaced by a "#" which allows people to discover your image(s). (For example, an image with "#fashion" in its caption will show up for everyone browsing the "fashion" tag.) (maximum of 30 hashtags)
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How-To Articles
A list of useful links for you:

Instagram Help Centre - Posting and Adding Locations
Official information on posting photos and videos on Instagram.
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