The challenge is to clearly differentiate between non-legato and legato, and between forte (f) and piano (p). In the forte sections, imagine a trumpet, playing each note clearly with accents. Visualizing tonguing on a trumpet will naturally lead to a non-legato expression. Be sure to consciously lift your fingers to prevent notes from connecting due to finger convenience. On the other hand, the piano sections have slurs, representing an echo. With a soft sound, imitate the melody played by the trumpet. Even when the articulation and dynamics change, maintain a consistent tempo. In practice or lessons, it could be fun to divide the trumpet and echo parts between a teacher and student, or among friends!