Scroll down to your own equipment, press the equip item button to give Malborn your equipment. Any item you dont want. By default, the R-key will give your items to him Hear this is a good explaination I found in a forum as my English sucks When you speak to him for the first time, just have the conversation as normal. He insults you a bit depending on your dialog choices (you can get revenge later if you wish), but then after you're done asking questions tell him you're ready and he opens his inventory. It works the same way (with the same buttons) as if you were storing items in your house. By default, the R-key will give your items to him. Give him everything you use for your quests: your armor, weapons, enchanted jewelry, everything. When you are done, go back to Delphine and she will give you a special outfit for the party and after you put it on she will take from you EVERYTHING that you did not give Mal. At the party you will see Mal again and after causing a bit of mischief he will return to you all the gear that you gave him. Credit to WoogieMonster on another forum