We do our best that we know how at the moment, and if it doesn't turn out, we modify it.

One thing is sure. We have to do something. We have to do the best we know how at the moment. If it doesn't turn out right, we can modify it as we go along.

You must do the thing you think you cannot do

Doing your best means never stop trying.

If you'd have it done, Go: if not, Send

It isn't sufficient just to want - you've got to ask yourself what you are going to do to get the things you want.