I made two cardboard templates - poking holes with a screwdriver.
The first template round, with a diameter slightly less than the container, so it will rest flat on the bottom.
Mark the wick-sticker locations with a sharpie; remove the template, and fix your wicks.
The second template is larger than the diameter so it can sit on top of the container;
after pouring, I'll feed the 6" wicks through the holes, gently pull 'em tight, twist as needed to ensure the wicks stand straight until the candle is dry.
While not fully necessary, I bend the wicks at 90 degrees on top of the template; this helps them stand straight and secure.