This pattern is for a 12 inch cushion cover.
Stitches used are: Tunisian Simple Stitch (TSS), Chain, Slip stitch (SlSt), Treble Crochet (Tr), Magic Ring.

The pattern might seem quite complicated for a novice at Tunisian crochet and I am no expert at writing Tunisian patterns but if you follow every step and read the pattern carefully I hope you will find it fairly straight forward.

TSS is made by a Forward Pass and a Return Pass. For the Forward Pass, insert your hook in the next vertical bar (or other stitch where stated) Yarn over, pull the hook back through to the front of the stitch. Carry on this way until the end of the Row or for the number of stitches stated. Return pass is made by yarn over and through the number of loops stated on your hook.
I have included some photos to help get you started and help you to recognise the vertical bars for the Forward pass of TSS.

You will need various colours of your choice of yarns. I have only tried this pattern with Double Knit weight yarn however I see no reason why it would not work with a different weight.
Tunisian Crochet is best worked with a loose tension, therefore use the hook size that suits your tension best, I use a 5mm hook with DK weight yarn.