Step 4. Launch Instagram on your device and log in if necessary, then tap the camera button to take a picture. Tap the button to the left of the camera button. In iOS, the Camera Roll will open. In Android, tap Gallery to open the Gallery.Tap the GIF image you want to post on Instagram. Crop the picture if necessary and then tap the forward button. Optionally, add effects to the picture and then tap the forward button again.Add a caption in the Caption box, tag people if necessary and choose the services on which you want to share the image.tep 4. Launch Instagram on your device and log in if necessary, then tap the camera button to take a picture. Tap the button to the left of the camera button. In iOS, the Camera Roll will open. In Android, tap Gallery to open the Gallery.