The best tool for poaching eggs is a Chinese colander.
(disclaimer — if you purchase it from the above link I make a small commission)
This colander is big enough to let you do up to 8 eggs at a time. The holes let you strain the liquid part of the white (I do this part in the sink). Then you gently lower the strainer into a large skillet with 1.5 inches of simmering salted water. Any skillet with 11+ inch diameter will work with this strainer. Depending on the shape of the sides, some 10 inch skillets fit it snugly too. Cook for 4 minutes at a bare simmer, remove to the paper towel and test for doneness. The yolk should feel like a water balloon. The white should be set.
To save the eggs for serving later, transfer them to a bowl of cold water and refrigerate. The best way to rewarm is 15 min at 140F water. If you don’t have a way to maintain steady 140F, bring a large skillet of water to a simmer. Take it off the heat. Add the eggs and let them warm up for 4 minutes.
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