Buy a good fountain pen, write slowly. Start by getting cheap pens, preferably those with interchangeable nibs to see which nib size you prefer using. When you know which size you like (for most people it will be medium) get a decent pen and nib and carry it with you.
I have a vintage Parker 51 and some oldish German pens. Modern Japanese pens are quite good though nibs can be narrow for Western taste.
After trying several fountain pens and having less than pleasant experiences, I have for years now used felt-tip pens almost exclusively. It approximates the look and feel of a fountain pen close enough for my tastes, and requires much less wrist pressure than ballpoint pens.
I have a vintage Parker 51 and some oldish German pens. Modern Japanese pens are quite good though nibs can be narrow for Western taste.