Picking up stitches for sleeve underarm

Working on my Frost Flower sweater, I thought l’d share with you the way I pick up stitches for sleeve underarm from the previously cast-on stitches for body underarm.
To avoid the gaps between “live” stitches on the needle and cast-on stitches, I pick up 2-3 extra stitches on both sides of cast-on sts and then decrease them in the next round to get the number of sts per pattern.