Let $U\subset\mathbb R^n$ be a bounded Lipschitz domain, let $p>n$, and let $u\in W^{1,p}(U)$. Then $u$ has a representative in $C^{0,\gamma}(\overline{U})$ with
\begin{align*}
\gamma=1-\frac{n}{p},
\end{align*}
and there exists $C>0$, depending on $U,n,p$, such that
\begin{align*}
\|u\|_{C^{0,\gamma}(\overline{U})}\le C\|u\|_{W^{1,p}(U)}.
\end{align*}