Before casting on, you need to calculate how many blocks you want in your fabric and how many stitches will be there in each block. Example, each block contains 6 sts, and each tier contains 5 blocks, so you cast on 30 sts.

For this tutorial, starts with 18 sts to be worked in three groups of 6.
THREE BASE TRIANGLES 
Row 1 (WS): K2, turn
Row 2: K2, turn
Row 3: K3, turn
Row 4: K3, turn
Row 5: K4, turn
Row 6: K4, turn
Row 7: K5, turn
Row 8: K5, turn
Row 9: K6, end of left triangle, do not turn
End of base triangle one of three, start next base triangle on next stitch
Rep Rows 1 to 9 two more to complete all three base triangles


TIER 1: 2 Diamonds and 2 Side Triangles 

Left Side Triangle 
Row 1 (RS): K2, turn
Row 2: K2, turn
Row 3: Kfb, SSK, turn
Row 4: K3, turn
Row 5: Kfb, K1, SSK, turn
Row 6: K4, turn
Row 7: Kfb, K2, SSK, turn
Row 8: K5, turn
Row 9: Kfb, K3, SSK, end of left triangle, do not turn
Now work the two middle diamonds of Tier 1.

Two Middle Right SLanting Diamonds 
With RC facing, pick up and knit 6 sts along the selvedge edge of the next triangle or diamond, turn.
Row 1: K6, turn
Row 2: K5, SSK, turn
Row 3: K6, turn
Row 4: K5, SSK, turn
Row 5: K6, turn
Row 6: K5, SSK, turn
Row 7: K6, turn
Row 8: K5, SSK, turn
Row 9: K6, turn
Row 10: K5, SSK, turn
Row 11: K6, turn
Row 12: K5, SSK,  end of Diamond One, do not turn
Rep Rows 1 to 11 one more time to complete all both middle diamonds. Once both diamonds are done began working the right side triangle in the next section.

Right Side Triangle 
With right side facing, pick up and knit 6 sts along the selvedge edge of the next triangle or diamond, turn.
Row 1: K6, turn
Row 2: K4, SSK, turn
Row 3: K5, turn
Row 4: K3, SSK, turn
Row 5: K4, turn
Row 6: K2, SSK, turn
Row 7: K3, turn
Row 8: K1, SSK, turn
Row 9: K2, turn
Row 10: SSK, and transfer this st to the right needle.
The remaining stitch will be counted as the first st picked up for the first diamond in Tier 2. .
TIER 2: 3 Diamonds 

Three Left SLanting Diamonds 
For the first diamond only, the remaining stitch from the last tier counts as 1 picked up stitch
With WS facing, slip 1, pick up and purl 5 sts along the selvedge edge of next triangle or diamond.
Row 1: P6, turn
Row 2: P5, P2tog, turn
Row 3: P6, turn
Row 4: P5, P2tog, turn
Row 5: P6, turn
Row 6: P5, P2tog, turn
Row 7: P6, turn
Row 8: P5, P2tog, turn
Row 9: P6, turn
Row 10: P5, P2tog, turn
Row 11: P6, turn
Row 12: P5, P2tog, end of Diamond One, do not turn
Pick up and Purl 6 sts along the selvedge edge of the next triangle or diamond.
Rep Rows 1 to 12 two more times to complete three middle diamonds. Once the three diamonds are done you will start tier one again.
Continue working TIERS 1 and 2 until the desired length is reached. 

BIND OFF TRIANGLES 
Before you begin the bind off triangles the last tier you work is tier one. 
With WS facing, slip 1 st, pick up and purl 5 sts along the selvedge edge of the next triangle or diamond. For the first triangle only, the st remaining counts as the first picked up stitch.
Row 1: P6, turn.
Row 2: P2tog, P3, P2tog, turn.
Row 3: P5, turn.
Row 4: P2tog, P2, P2tog, turn.
Row 5: P4, turn.
Row 6: P2tog, P1, P2tog, turn.
Row 7: P3, turn.
Row 8: P2tog, P2tog, turn.
Row 9: P2, turn.
Row 10: P2tog, P2tog, pass 1st st over 2nd, do not turn.
The remaining stitch will count as the first stitch of the next triangle.
When all three triangles have been worked, bind off last stitch and weave in ends.