Update README.md

Author: Iddingsite

README.md

@@ -14,6 +14,22 @@ Currently, the package focuses on non-conservative form of the advection terms (
 
 The core of the package is written in pure Julia, focusing on performance using CPUs but GPU support is available using KernelAbstractions.jl and Chmy.jl via 2 separate extensions.
 
+## Installation
+
+FiniteDiffWENO5.jl is a registered Julia package and can be installed directly using the package manager:
+
+```julia-repl
+julia>]
+  pkg> add FiniteDiffWENO5
+```
+
+And you can test the package with:
+
+```julia-repl
+julia>]
+  pkg> test FiniteDiffWENO5
+```
+
 ## Features
 
 The package currently exports only two main functions: `WENOScheme()`, that is used to create a WENO scheme struct containing all the necessary information for the WENO method, and `WENO_step!()`, that performs one step of the time integration using the WENO-Z method and a 3rd-order Runge-Kutta method. The grid and the initial condition must be defined by the user.