Have maven installed in your computer
Use the following command, gradle (or using wrapper,i.e ./gradlew) clean publishToMavenLocal
Check first if the .aar is inside your .m2 directory. Second, in order to use this library in a client app, and mavenLocal in your project build.gradle file
allprojects {
repositories {
mavenLocal()
google()
jcenter()
}
}