1. Update version number of clover-maven-plugin in your pom.xml
2. Update version number of clover dependency in your pom.xml (optional)
Your pom.xml may contain a dependency to Clover Core (com.atlassian.clover:clover). Update it's version number the same version as the clover-maven-plugin:
3. Update license key (optional)
Installing new license is necessary if you're installing a Clover version released after end of support date of your current license.
4. Delete existing coverage databases (optional)
Clover's database format may change in newer versions. In such case you may get a build error with a message informing about database incompatibility. In such case you have to delete old database files.
By default, databases are stored in module's /target directory; thanks to this incompatible databases are removed automatically upon 'mvn clean'.