Cold water is best for bloodstains as blood will break down and dissolve. Warm or hot water will literally "cook" the blood and the stain will become more difficult to remove.
Remove as much blood as possible with cold, clean water. Remember to apply water from both sides of the fabric.
Avoid smearing the blood around wherever possible. Blot the stain with a wet napkin.
Bloodstains are often only discovered once they've dried into fabrics. If you've ever had a bloodstain on your clothes you'll know how hard it is to get out. People often assume that cuts, scrapes and nosebleeds can ruin clothes, however, Vanish Oxi Action is always on hand to make removing blood stains easy.