All XOF patches can be collected during the main mission "Ground Zeroes".
1: At the edge of the cliff, behind the starting point.
2: In a trashpile in the West Refugee Camp. This is in front of the shed to the south.
3: On top of one of the generators north of the warehouse area
4: On top of the guard house north of the Old Prison Camp.
5: Found immediately as soon as you unlock the prison camp gate.
6: Opening of the drainage system, behind some crates and boxes, a few distance away from the red door to the northeast of the Administration Building.
7: Enter the northeastern red door and climb up the generator units and leap to the ledge. Find the next patch beside an exhaust tip.
8: Check the ground of the helipad with a black patch, beside an electrical block to the west to find this patch.
9: Behind Snake's back bag.
Go prone on the ground and start rolling from side to side. A scene will trigger showing how the patch got in there in the first place. Once it is dislodged, pick it up