Add punctuation: After attaching the SD card launch the app from the Applications Folder
A: After attaching the SD card, launch the app from the Applications Folder

Add punctuation: His chair of pure mathematics was however a little unfortunate as Jeffrey had to leave many parts of that subject to his assistants
A: His chair of pure mathematics was, however, a little unfortunate as Jeffrey had to leave many parts of that subject to his assistants.

Add punctuation: The iceman carried a simple pack frame on which he could carry heavier loads on his back
A:
The iceman carried a simple pack frame on which he could carry heavier loads on his back.