Start of another shawl

Here is the centre panel for another Shetland HapI have started- not sure why I keep making them - must enjoy it I suppose...? I start by casting on three stitches and then increasing one stitch at the beginning of every row until there are 111 sts. I then knit two more rows before starting to decrease 1 st. every row until I get back to three stitches on the needle. I shall incorporate some of the colours in the wavy Old Shale pattern which is the next stage.