Add beginner-level documentation for installation and use

README.md

@@ -24,6 +24,24 @@ One could also use a standard Clang installation, build a sysroot from the
 sources mentioned above, and compile with
 "--target=wasm32-wasi --sysroot=/path/to/sysroot".
 
+## Install
+
+A typical installation from the release binaries might look like the following:
+```shell script
+wget https://github.com/CraneStation/wasi-sdk/releases/download/wasi-sdk-[version]/wasi-sdk-[version]-linux.tar.gz
+tar xvf wasi-sdk-[version]-linux.tar.gz
+sudo cp -r wasi-sdk-[version] /opt/wasi-sdk
+```
+
+## Use
+
+Use the clang installed in the wasi-sdk directory:
+```shell script
+PATH="/opt/wasi-sdk/bin:${PATH}"
+clang foo.c -o foo.wasm
+```
+Note that, with this installation, the used includes/libraries/etc. are in `/opt/wasi-sdk/share/wasi-sysroot`.  
+
 ## Notes for Autoconf
 
 Upstream autoconf now