How formally to prove commutativity of disjunctions with natural deduction?

Question

How do I formally prove that $p \lor q$ can be written as $q \lor p$ using natural deduction? I realize this may very well be trivial but still can't properly prove it.

Answer 1

From proofs.openlogicproject.org

Answer 2

You can derive $\psi\vee\phi$ from $\phi$ and also from $\psi$. Therefore, you can derive $\psi\vee\phi$ from $\phi\vee\psi$.