I wouldn't worry about keeping in a strict K2 P2 pattern from the start of the row. If you always start w/ k2 (or P2 for that matter), you'll mess up the ribbing once the incs begin. So just purl the knit sts and knit the purl sts as you come to them. And remember that when you've inc'd to an odd number of sts, you will have to end or begin a row with K1 (or P1), then continue with the 2x2 rib.
I just casted on 8 sts.
row 1 = k2, p2 across
row 2 = k2, p2 across
row 3 = k1f&b, k1, p2, k2, p2
row 4 = k2, p2, k2, p2, K1
row 5 = P1, *k2 p2, *rep across
row 6 = p1f&b, *k2, p2, *rep across
row 7 = k2, p2 across
row 8 = P2, k2 across (10sts - you are now back to an even 2x2 rib BUT, you are starting with P2, instead of K2.)
Hope that helps