Focus your gaze in a relaxed way on the mandala, at the same time as you in your minds eye connect with your entire being, your spine, your heart or your 3’ eye it relates to, and ponder the contemplation that belongs to it.

This is called double-poled awareness, and is a classical technique to enhance meditation (used in the western spiritual traditions for example on Christian Icon’s, in the east for example on mandalas of deities, the Thangka’s)

The idea is that when the two directions of thought - towards the image and towards for example the reference point in your body, when these two directions are of equal strength, a qualitative leap will happen. The mind will be suspended and a meditative state is experienced. This will most likely happen only in fractions of a second at a time, with the normal mind taking over in between