diff --git a/README.md b/README.md
index 0356c6b..b5e2a4c 100644
--- a/README.md
+++ b/README.md
@@ -1,72 +1,76 @@
-WIP
-
 # The PSI Spack Deployment
 
 ## How to use on Merlin7
 
+### Install your own software
 ```bash
-source /afs/psi.ch/sys/spack-rhel7/spack/share/spack/setup-env.sh # can be also include in your .bashrc
+# Check if your package is already in Spack
+user@login001:~> spack list $pkg_name # e.g opal
 
-spack env list
-spack env activate -d <package> # e.g ffbidx all for whole software stack
+# Check the package variants you want to set e.g +cuda +openmp ^openmpi ...
+user@login001:~> spack info $pkg_name # e.g opal
 
-# Install env if local development, else skip
-spack install # -v for verbose
+# Check the whole dependency tree of your spec and 
+# if you don't need to set more variants
+user@login001:~> spack spec $pkg_name@version +variant1 ^dep1@version ...
 
-spack load <package>
+# e.g spack spec opal@2022.1%gcc@7.5.0 +mithra ~python ^openmpi@4.1.6 ^openblas
+
+# Install your package
+user@login001:~> spack install $pkg_name@version +variant1 ^dep1@version1
+
+# Load your package
+user@login001:~> spack load $pkg_name@version +variant1 ^dep1@version1
+
+# Submit your script
+user@login001:~> sbatch batch.script
 ```
 
-## How to use on Merlin6
+### Develop your own software
+```bash
+# Check if your package is already in Spack
+user@login001:~> spack list $pkg_name # e.g opal
+
+# Check the package variants you want to set e.g +cuda +openmp ^openmpi ...
+user@login001:~> spack info $pkg_name # e.g opal
+
+# Create your own env and load it
+user@login001:~> spack env activate --create -p myenv
+
+# Add the spec you want to build to your environement
+user@login001:~> spack add $pkg_name@version +variant1 ^dep1@version ...
+
+# e.g spack add opal@master%gcc@7.5.0 +mithra ~python ^openmpi@4.1.6 ^openblas
+
+# Tell Spack you want to develop locally under
+# /afs/psi.ch/sys/spack.x86_64_cos3.0/user/$USER/spack-environment/$pkg_name
+user@login001:~> spack develop $pkg_name@version
+
+# Install the package locally
+user@login001:~> spack install # first time, then you can just use make directly
+
+# Load your package
+user@login001:~> spack load $pkg_name@version +variant1 ^dep1@version1
+
+# Submit your script
+user@login001:~> sbatch batch.script
+
+```
+
+## How to use on other systems
+
+### Install Spack
 
 ```bash
-source /afs/psi.ch/sys/spack-rhel7/spack/share/spack/setup-env.sh # can be also include in your .bashrc
+user@supersystem:~> cd /scratch/$USER
 
-spack env list
-spack env activate -d <package> # e.g ffbidx all for whole software stack
+user@supersystem:~> git clone -c feature.manyFiles=true https://github.com/spack/spack.git
 
-# Install env if local development, else skip
-spack install # -v for verbose
-
-spack load <package>
-
-# The OPAL Spack recipe
-
-[Official Spack documentation](https://spack.readthedocs.io/en/latest/)
-
-## Install Spack
-
-```bash
-cd /scratch/$USER
-git clone -c feature.manyFiles=true https://github.com/spack/spack.git
-. spack/share/spack/setup-env.sh
+user@supersystem:~> . spack/share/spack/setup-env.sh
 
 # Add PSI specific recipes
-cd OPAL/spack
-spack repo add .
-```
+user@supersystem:~> git clone https://gitlab.psi.ch/lsm-hpce/alps/spack-psi.git
 
-## Install OPAL@version
+user@supersystem:~> spack repo add $PWD/spack-psi
 
-```bash
-spack info opal # Find out which version and which variants you want to set
-
-# Install env if local development, else skip
-spack install opal@2022.1.0 # -v for verbose -j 8 for 8 parallel jobs
-
-# Load environment before launching any scripts
-spack load opal
-
-sbatch ...
-```
-
-## Develop OPAL
-
-```bash
-spack env activate -d OPAL/spack/env/opal/
-
-# $OPAL_SRC_DIRECTORY is where you did the git clone git@gitlab.psi.ch:OPAL/src.git
-spack develop -p $OPAL_SRC_DIRECTORY opal@master
-
-spack install # -v for verbose -j 8 for 8 parallel jobs
-
-```
+user@supersystem:~> spack install $pkg_name # -v for verbose