To better understand plating and to get inspired to use this technique, try the following exercise with different yarns.
Set your tension dial to a looser tension (how loose? It depends on the yarn you've chosen)
Using 2 strands of yarn,(not too heavy! - 1/2 the weight you'd usually use with your machine)
Cast on 30 stitches. Use any method you'd like, but add even weight.

With BOTH STRANDS in the #1 (main) yarn feeder, knit a few inches.
- Is it hard to knit? - USE a thinner yarn
- As you knit, feel the resulting knitting and judge the tension - adjust as you like.

Re-thread the carriage - putting one yarn in each slot
- Knit a few inches
- Note which color yarn is facing you as you knit (the purl side of the knitting)

Reverse the yarns in the feeders
- Knit a few inches
- Note which color yarn is facing you as you knit (the purl side of the knitting)

Repeat this exercise with different yarns in both color, weight and texture.
Get Creative!