The signature of these three words can refer to the following ways:

1, simple and generous: choose a simple and generous font to make the word "Du" look neat and clear. You can consider using straight lines and simple curves to avoid too complicated decoration.

2. Use Lian Bi: Use Lian Bi's technique to naturally connect letters between the words "all uppercase and uppercase". This can increase fluency and artistic beauty.

3. Emphasize individuality: by making some changes in the font or adding some special decorative elements, highlight the personality characteristics of the signature "Du". You can refer to some interesting fonts or handwriting styles and add your own unique ideas.