How to remove blood stains?

Love your daily article in our local newspaper (Waco, Texas). If there is one article that I definitely read every day, it’s yours. 
I had meant to cut out the article about how to get rid of blood stains – even though the article had been through the dryer and I forgot to do it!  My daughter’s favorite pair of shorts are stained, and I have tried quite a few remedies, but cannot for the life of me remember what advice you gave. I am almost sure that it was a paste of baking soda and something else??
 
Please help!
 
Thanks so much.  Keep up the good advice.