What is the best way to install these? Should they have come with adhesives for the vertical plastic peices on the matching base cabinets?

Thanks for reaching out to us. Installation methods can vary. We do not included adhesive with the panel. It can be attached with small finishing brads or pin nails and set the brads or pins with a small nail set. Next putty the small holes using a matching fill stick. Adhesives or wood glue can also be used to secure the toe kick. Thanks ~ Sherri