How to use bluing tablets?

[Nick D]

I just bought some Reckitt's bluing tablets, but the directions are very sparse. What I want to use the blue on is my detachable collars, several of which are old and a little yellowed, and a couple of my white shirts. I thought I should wash by hand (which I usually do with the collars anyway), but I'm not sure how much rinse water to use with the blue. Should I use a whole tablet in a bathtub half full? I've read that you shouldn't use too much blue.

 

[Lokar]

With the blue I have, you wrap the tablet in cotton or muslin, stir it while squeezing into the last rinsing water, and then briefly dip each item into the water one at a time. There's no volume information, unfortunately...

 

[davestlouis]

I've always used liquid bluing, and even being very careful, wound up with white items that were visibly blue...be VERY careful with it.