Spiritual wellness is about being connected spiritually and having meaning and purpose in your life. It's about making time for spiritual activities and/or things that make you grow as a human being - e.g. for praying, for singing, for meditating, for reflecting, for going to church and for doing faith based work.
It has many facets. The following figure lists six of the most important ones - none is more important than the other and there is no hierarchy implied by each one's position!