To equip quality or rare gear caliber is the first step in the process. If that is important to you, you may want to fill in a couple of purity items for the resistance stats. No normal equipment should be in work, the reason behind is the rarity boost drop rates. This should increase your chances for success in farming Chaos Orbs significantly. When you finish equipping quality, rare or purity items and you can proceed to the Church Dungeon then Fellshire Ruins. In this location you can farm blue and rare items, and nothing else. If you're hard-pressed for currency items, then go ahead and loot whites, otherwise, only focus on blues and rares. For skills, in the quickest time to slaughter mobs is your goal, the same as other MMORPG's. With that being said, use AoE (Area of Effect) or high-damage skills for efficiency is the best way for you. Now and then rare items may drop. By typing in the chat box you can check the item level for each you obtained. https://www.mmogah.com/news/poe/what-are-the-best-ways-to-get-chaos-orb-in-path-of-exile