What is a one-sentence summary of the following article?
If you're already logged into Instagram, doing so will open your Instagram Home page. If you aren't logged into Instagram, type in your username (or phone number) and password and tap Login. It's in the bottom-center of the screen. You should see this option in the bottom-left corner of the screen. It's the rightmost grey circle on the middle-right side of the screen with two overlapping cubes in it. If you don't see this option, you may need to update your app. You can select up to ten photos. It's in the top-right corner of the screen. If you don't choose a filter, your photos will not be altered. Filters are arranged at the bottom of the screen. Selecting one filter will apply it to all of your photos in this group. It's in the top-right corner of the screen. This option is in the top-right corner of the screen. Doing so will share all of your photos to Instagram at once. You'll be able to view them by swiping left or right over the displayed photo to scroll through the group.

Summary:
Open Instagram. Tap +. Tap Library. Tap the "Select Multiple" icon. Tap each photo you wish to upload. Tap Next. Tap a filter if you wish to add one. Tap Next. Tap Share.