The "add to mash, not the water" trick. Personally I was suspicious of this as you have no idea what you've actually done (can't see it <EDIT: of course I "can't see it" … I should have made it clearer that I'm talking "figuratively">). But if you have the confidence then not a problem (if Graham was still about we'd have the confidence - he could be "very persuasive"!).
Which is a point: You should add calcium hydroxide (mentioned by "Silver_Is_Money") to the mash, not the water, too, but for an entirely different reason which I hope we don't have to go over again (the forum's "instructor" on this that comes to my mind isn't so much "persuasive" as "abusive").
I noticed Graham mentioned "sodium carbonate" in his "Note 9" but didn't think it was such a good idea. I do use sodium bicarbonate (it does dissolve - I'm one of the minority UK homebrewers who does need to add alkalinity to his water and to increase the pH) but am of the belief "sodium carbonate" will dissociate into sodium and bicarbonate in the mash anyway? Sodium bicarbonate (baking soda) is much easier to get your hands on.