Apple-cider vinegar has many health benefits (including aiding in weight loss) and can be used both internally and externally, as well. However, it is very strong, so it is not recommended that you apply it directly on the skin. It will kill the yeast, but it will burn. The best way to apply is to add a cup of it into your bathwater and take a nice hot bath. This will help soothe the itching and burning. 
The type of vinegar I recommend is Bragg's Apple Cider Vinegar, with the Mother. It is important that it have the mother, as this is more natural and less processed. Never use plain, white vinegar! This actually feeds the yeast instead of killing it. Taking apple cider vinegar before you eat will also aid in weight loss.