![Rolling Eyes :roll:](./images/smilies/icon_rolleyes.gif)
I've found the type of lighting you use is very important, and not all people have the ability to see the same.
I have a buddy that has one of those "blood trailing" lights, and he can spot drops of blood easily - I can't see the blood with it!
I use a light with a Cree XP-E LED (Fenix HL20 and can spot blood easily with it.
I'd suggest trying a few different type of illumination when you follow along as your buddy helps. You might find something that will work for you.
Edited to add:
BTW - Don't only look for color, look for texture, too. Moist blood drops on a dry surface can really stand out because they shine.
![Wink :wink:](./images/smilies/icon_wink.gif)