Drain olives and place them in a large bowl.: The bowl of olives should look glossy once drained, and you may hear a faint glug as the brine settles. Draining removes excess salt so the marinade can control seasoning, and placing them in a roomy bowl makes it easy to stir. A common mistake is not draining enough, which results in an overly salty final dish.
To the olives, add the oregano, rosemary, thyme, garlic, red pepper flakes, orange zest, and lemon zest. Add salt, as needed (See NOTES).: Once the aromatics hit the bowl, you will notice an immediate lift in scent, citrus cutting through the brine. Stirring at this stage helps the dried herbs begin to hydrate and the minced garlic to release its essential oils. Be careful not to over-salt, taste as you go. A typical error is adding too much salt early, which cannot be undone.
Add enough oil to coat the olives, about 1/2 cup. Gently stir the olives with the aromatics until they are fully coated. If possible, transfer the olives to a large jar with a lid, or a couple of smaller jars with lids. Add more oil to just cover the tops of the olives. If keeping in the bowl, cover with plastic wrap, if using jars, screw on the lids.: As the extra-virgin olive oil envelops the mixture, you will see a sheen form on the olive skins and tiny herb flecks suspended in the oil. This oil not only distributes flavor but protects the olives in storage. When transferring to jars, tap them lightly to release air pockets. A common slip is using too little oil which leaves herbs exposed to air and causes uneven marinating.
Place in the refrigerator for 12 hours, or preferably 24 hours, or up to 1 month. Before serving, allow the olives to come to room temperature, a couple of hours.: During refrigeration the flavors meld and the oil thickens slightly, which concentrates aroma. After resting, bring the olives to room temperature so the oil loosens and scents bloom, releasing citrus perfume and softened herb notes. Avoid serving them straight from the fridge, which mutes flavors. One mistake people make is not waiting long enough for the flavors to marry.
To serve, pour the olives with the oil into a large bowl. Use a slotted spoon to place the olives in a serving bowl. Scoop out some of the herbs, zest, and garlic from the oil and drizzle over the olives. If serving whole olives, be sure to include a bowl for guests to place the pits.: When you spoon them out, the sound of oil sliding is subtle and inviting, and the herbs glisten on top. Drizzling some of the infused oil back over the olives intensifies the aroma and creates a luxurious mouthfeel. Offer a pit bowl to keep the presentation tidy. A frequent oversight is not reserving enough oil, which reduces the ability to dress the olives when plating.