While it seems natural and easy, sex is not always so the first time.
Mechanically it is not hard, but a lot of thing can be mentally hard. The anticipation, the anxiety, expectations.. There are high risks to not perform at its finest.
Knowing himself and knowing herself, knowing our bodies and what we need to fee good helps in doing the right thing for ourselves; knowing how we can feel good can help in knowing how, at least, helping someone feel good.
For how much a "first time" would be romantic, I have this convinction that a "disaster" or a "fail" would not be a so romantic "once in a lifetime gift".
Plus, having to do it with an u experienced person, I swear, is pretty hard. It is almost a job where you have to take care of the other person so much that there is little room for your needs. That if you care for the other one.
To gwt back in the topic: pretty positive discussion. Taking into account other people accident can be quite positive into thinking that it is somewhat part of normality and minimize the embarrassment coming from memories.