As in the title, the question is
Give a natural deduction proof of $\varphi\vdash\top$, where $\varphi$ is any formula.
Could I do this proof by deriving $\varphi \rightarrow \top$ with $ \rightarrow$-introduction rule which says that if you can derive a formula $\psi$ from a formula $\varphi$, then $\varphi \rightarrow \psi$ is true. So, with this derivation I will use $\varphi$ as an assumption and derive from $\varphi$, or am I thinking wrong? I prefer hints before solution!