Use the following trick to store items that you do not want to carry in your inventory. Enter the Inn in Skellige and go to a corner in the room. Drop all your items at once and will appear as a bag on the floor. You can return to retrieve them whenever desired. To add something else to the pile, pick up the bag, and then drop it again after it has the additional item.
The environment can be used in several ways to kill enemies.
The first contract available is "The Devil by the Well" in White Orchard, but may be difficult to complete without using oils and signs. Instead, consider doing this on the griffin in White Orchard. It is an easier fight, and will count as a contract even though it is required by the main questline. Another option is the werewolf at Velen during the "Wild At Heart" secondary quest. Although the quest does not appear as a contract in the journal, it also counts.
When you complete the "Ugly Baby" main quest, the side quest "Brothers in Arms" will start. The required people can be found as follows. Note: Letho is optional, because he may have already been killed due to events from The Witcher 2.