You must use cold water if you are going to successfully remove blood stains from clothes and other (washable) fabrics. Hot water will cause the stain to set permanently, and it will be a nasty, dull brown color, not even bright red anymore.
Hydrogen Peroxide is great for getting out fresh bloodstains (though it won’t work on set-in stains), but you’ve got to get to the stain quickly. You can get it in your local grocery store, usually in the pharmacy / medicine area or thereabouts. I’ve always seen the hydrogen peroxide come in cylindrical, brown bottles. It’s fairly cheap, too.
Just use it straight out of the bottle. Pour an amount directly on the stain, saturating it, and watch it bubble the blood right out of the fabric. Rinse with cold water, and pour on more if there is still blood stain present, until the stain is gone.
It’s also good for pouring on (minor) cuts and scrapes, to cleanse them; it will bubble up. Afterward, you’d still be wise to apply some antibacterial ointment (Neosporin or Bacitracin are good, or some Neosporin-like, generic product such as triple-acting antibiotic ointment) and bandage it up. Pouring rubbing alcohol on a wound will cleanse it, but is painful as hell. ugh!