Complex sentence: Once a core is decided upon, a layer of foam padding is glued around it, or a core could be inserted into a pool noodle, either full length or cut into smaller pieces, which makes a firm, yet safe coating for the weapon.
Split into simpler sentences: Once a core is decided upon, a layer of foam padding is glued around it. Sometimes a core is inserted into a pool noodle, either full length or cut into smaller pieces, which makes a firm, yet safe coating for the weapon.