The Lord's Supper is a Christian rite or ceremony that is commanded or instructed to be done by the believer in remembrance. In other words it is to memorialized and remind us of what Jesus Christ does and is doing for us. To the extent that it reminds us of the role and function that Christ plays in God's plan it is effectively doing its job.
To me this is clear and simple. There is something we are to do. How it is to be done is seemingly not clear. There are various ways the Lord's supper instruction is followed in the various Christian communities.
The elements of the ceremony are symbolic. That, surely, is clear. I see it in a rather simple light. The important thing is that we remember what Jesus Christ did for us. I see the application of the symbols and acts of the rite as clear and simple.
I explain the symbolism in the Lord's supper using the following points.
What SDAs Believe About the Belief and Practice of the Lord’s Supper
Communion, The Lord’s Supper, or Eucharist? (Michael A. Milton)
A Reformed and Confessional View (Rhett Dodson)
A Foretaste of the Heavenly Banquet (Bobby Jamieson)