Cutting:
Seam allowances are included - 1cm wide or as per marking clips!
Cut out the pattern pieces from your outer fabric. Lay the fabric right side up. Place the selvedges parallel to the center so that you can place the front, back, and front yoke on the fold. The pattern pieces should all be laid with the writing facing up. Always align the grain arrow on all pieces in the same direction and parallel to the selvedge of the fabric. Transfer all notches from the pattern by making a 3mm long slit with scissors or chalk and mark the ends of the darts from size 40 onwards for the plain version. Note that bust darts are required for larger sizes. For the version with pleats, the dart is omitted completely. Notch the seam allowance on the fold, as this is always the center. Marks define the positions of dart ends, pocket positions, and much more. Transfer these either with chalk or pins. 
To sew this sweater you will need a sewing machine and an overlock sewing machine, or alternatively the zigzag stitch on your sewing machine to neaten the cut edges.
Be sure to use a jersey needle and a stretch stitch. This means that if you're using a home sewing machine, you should use either a zigzag stitch or a three-part stretch stitch. Then, finish all seam allowances with a zigzag stitch or another similar stitch to prevent fraying. The colored lines in the images show you, in addition to the description, where a seam needs to be sewn or glued.
When sewing, pay attention to the seam allowance included in the pattern.
Have fun sewing! 
First, neaten the side edges of the front and back pieces, as well as the sleeves. 
Next, place the pleats in the front piece and sew them in place using the quilting foot. 
Then you can sew the front yoke and the front piece together, right sides together. Neaten the seam allowance and press it upwards. 
Now you can sew the front and back pieces together at the shoulders, right sides together, and neaten the seam allowances together. Press the seam into the front piece. 
Next, you need the collar. Sew it together right sides together, iron the seam open, and fold the collar together so the seam is tucked in. 
Now you can insert the collar into the neckline. Pin it in place, right sides together (the seam is pinned to the center back) and sew all the way around. Neaten the seams together again. 
Your piece is wide enough for you to insert the sleeve. Place the sleeve, right sides together, at the appropriate armhole (the notch in the front piece must align with the notch in the sleeve) and sew it in place. Neaten the seam allowance again and press it into the sleeve. 
Now you can sew the side seam together and press the seam open. A tip: I recommend pressing the seam allowance of the hem inward first. 
Now all that's left are the cuffs. Sew them together, right sides together, and then fold them over so the seam allowance is on the inside, just like on the collar. 
Sew the cuffs to the sleeves, right sides together. Make sure the cuff seam and sleeve seam line up. 
Finally, just sew the hem.
