From Jim Humble's 2011 ebook:
"To Make a 50% Solution of Citric Acid
Pack a cup or small bowl with citric acid powder (crystals), tamping it down to fill air holes. Dump it in a larger bowl. Then fill the same cup or small bowl with distilled or purified water and dump that in the larger bowl. The citric acid powder weighs almost the same as water and is close enough for the purpose. 75g each will fill a 4fl.oz. bottle.
Stir till dissolved. You will notice that the mixture becomes cold. Then pour it into a bottle(s) with a drip style top for counting drops and label it 50% citric acid. Use it for activating MMS at one drop for each drop of MMS. The best idea is to add some food coloring like the food coloring for cakes and other food purposes. This then keeps you from mistaking if you have citric or MMS in your glass. The food coloring in the citric will fade out when you add it to the MMS. But the coloring helps you know if what you spilled on the table is citric or MMS.
Whichever strength of citric acid you make, always store it in a bottle with a lid. When using citric acid as an activator, be sure to keep in mind all of the other instructions concerning how to mix and take MMS. To fill a 4 fl.oz. bottle mix 75gm each H2o & citric acid crystals."
