[Row 1]: 2ch, dc/sc in each of the next 2 tr/dc below, 15ch, insert hook through two loops of dc/sc and make sl.st, 1dc/sc in each of the next 3tr/dc below, 4ch, work 1tr/dc + 3ch + 1tr/dc in 4th tr/dc below, 3ch, 1tr/dc in tr/dc, 4ch, 1dc/sc in the same tr/dc, turn.

[Row 2]: 3ch, *1tr/dc + 1ch in space of 4ch; rep from* 7 more times, 1tr/dc in tr/dc, 2ch, 7tr/dc in space of 3ch, 3ch, 1dc/sc in each of the next 3 dc/sc below, turn.

[Row 3]: 2ch, dc/sc in each of the next 2 tr/dc below, 4ch, work 1tr/dc + 3ch + 1tr/dc in 4th tr/dc below, 3ch, 1tr/dc in tr/dc, 3ch, work 1tr/dc + 2ch in each of the next 7tr/dc of the shell, 1tr/dc in last tr/dc of the shell, turn.

[Row 4]: Work 1dc/sc + 3tr/dc + 1dc/sc in each of the next space of 2ch, 2dc/sc in space of 3ch, 2ch, 1tr/dc in tr/dc, 2ch, 7tr/dc in space of 3ch, 3ch, dc/sc in each of the next 2 dc/sc below, 1dc/sc in 2nd ch, 2dc/sc + 23tr/dc + 2dc/sc in ring of 15 ch, 1dc/sc in each of the next 2dc/sc below, 1dc/sc in 2nd ch, turn.

Repeat rows [1 – 4] one more time.

[Row 9]: 3ch, 1tr/dc in each of the next 2 dc/sc below, 15ch, insert hook through two loops of tr/dc and make sl.st, 1tr/dc in each of the next 3dc/sc below, 3ch, work 1tr/dc + 3ch + 1tr/dc in 4th tr/dc below, 3ch, 1tr/dc in tr/dc below, 4ch, 1dc/sc in the same tr/dc, turn.

[Row 10]: 3ch, *1tr/dc + 1ch in space of 4ch; rep from* 7 more times, 1tr/dc in tr/dc, 2ch, 7tr/dc in space of 3ch, 2ch, 1tr/dc in each of the next 3 tr/dc below, 2dc/sc + 23tr/dc + 2dc/sc in ring of 15 ch, 1tr/dc in each of the next 2tr/dc below, 1tr/dc in 3rd ch, turn.

[Row 11]: 3ch, 1tr/dc in each of the next 2 tr/dc below, 15ch, insert hook through two loops of tr/dc and make sl.st, 1tr/dc in each of the next 3tr/dc below, 3ch, work 1tr/dc + 3ch + 1tr/dc in 4th tr/dc below, 3ch, 1tr/dc in tr/dc, 3ch, work 1tr/dc + 2ch in each of the next 7tr/dc of the shell, 1tr/dc in last tr/dc of the shell, turn.

[Row 12]: Work 1dc/sc + 3tr/dc + 1dc/sc in each of the next space of 2ch, 2dc/sc in space of 3ch, 2ch, 1tr/dc in tr/dc, 2ch, 7tr/dc in space of 3ch, 2ch, 1tr/dc in each of the next 3 tr/dc below, 2dc/sc + 23tr/dc + 2dc/sc in ring of 15 ch, 1tr/dc in each of the next 2tr/dc below, 1tr/dc in 3rd ch, turn.

Now your corner has 3 big shells.

Continue crocheting edging. Repeat rows 3 – 6 (of the edging!) until you get the next corner.