Baby sweater pattern

[kmconboy]

Hello! I'm working on my first baby sweater, and just had a quick pattern question-
HEM (5 rows garter across 39stiches)
next row: K4 (p1, k4) to last 5sts, p1, k4
next row: P to end
These 2 rows set the part.

I understand the above part, but I'm getting stuck on the next part:
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Work a further 10 rows.
Inc and work into part one st at each end of the next row and every foll 4th row until there are 63 sts.
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I really just need some help understanding what this means. Thanks so much!

[suzeeq]

Your pattern is k4 then (p1, k4) to the end and, p1, k4 on the RS. So when you increase sts, you need to keep the p1, k4 sts. On th