I think that the best method is little and often because vitamin c has a fairly short half life of 3 hours if I remember correctly. Therefore taking small amounts of say 3grams every few hours would provide the most benefit. DO NOT take very large doses all in one go because it can cause problems with histamine release. That is meant to happen with doses of around 4 grams which is why I suggested 3 grams at a time.
This should benefit your circulatory system and your skin. You could make a drink bottle and calculate the amount and drink the bottle over a few hours. The only real upper limit is your bowel tolerance. If your bowel becomes loose then you are taking too much!
A good addition is black/blue/red berries which provide additional benefits as the proanthocyanidins strengthen the circulatory system, skin and bones.