Go to Payon
Talk to Bloto Ugarte (Equipment Socketing NPC).
The NPC will ask you to bring 11 items. 1 item will be converted to  slot and others will be consumed by the NPC.
1x Glove  (will become slotted).
10x Glove  (will be consumed by the NPC).
100,000 – 150,000 zeny (Depends on the items but mostly that is the range).
Product = 1x Glove