Doing your best means never stop trying.

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

Better slip with foot than tongue

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.

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

I am for doing good to the poor, but I differ in opinion about the means. I think the best way of doing good to the poor is not making them easy in poverty, but leading or driving them out of it.