Hi goldensun2210,
I think you know what is your problem but not very sure that what's the reason for it, i mean is it stress, bad sexual experience before or anything else.
Never mind, u asked for tips or any supplements helps erecting so there are some products available which claims for the same. But I think as your body is a part of this nature so why treat it with some artificial medicines.
Some of my friends have tried some herbal pills which are sexual health enhancer. There are herbal pills available for better erection. My friends are very much satisfied with the result and they are saying it really works and the best part of it is those pills don't have any side effects as they are made up of herbal ingredients.
So all the best and can tell me for further more information.