To use the 2:1 ratio measurement, locate the markings on the cup which relate to a 2:1 mix ratio. You will see numbers on stepped lines which run from '1' to '5'.
To measure A-side resin at a 2:1 mix ratio, simply fill the cup with resin to a numbered mark on left side of the scale, and then add B-side hardener until you reach the same numbered mark on the right side of the scale. You simply match the numbers.
NOTE: The A-side resin is always the number on the left and the hardener B-side is always the right number.
To use the 1:1 ratio measurement, locate the markings on the cup which relate to a 1:1 mix ratio. Simply pour equal amounts of A-side resin and B-side hardener. Example: For 20 ounces of mixed epoxy, simply fill A-side resin up to the 10 oz. mark and then fill up to the 20 oz. mark with B-side hardener.
These epoxy mixing cups are made from a polymer plastic which means that cured epoxy resin will not easily stick to them. Simply allow the epoxy to cure in the cup then flex and roll the cup to crack and break away the hardened epoxy. The cured epoxy peels away for multiple uses.
Please note that although the cups can be re-used in this way, they are only thin-walled and so occasional breakages should be expected.