This awesome Busy Kid Bib T-Shirt Pattern was written by Elles of Misusu Patterns. It is a great example of the excellent quality and style of all their patterns.

BIB T-SHIRT PATTERN + TUTORIAL
Hello! This is Elles from Misusu Patterns, and I’m very excited to share this versatile bib t-shirt pattern and tutorial with you! This t-shirt is the perfect addition to your kid’s back to school wardrobe – because of the relaxed fit and the front closure, it’s super easy to put over those busy heads! The pattern ranges from size 0-3 months (62) to 5-6 years (116). 
Before you get started, download the pattern & tutorial. Open the pdf, preferably in Adobe Acrobat Reader. To print the pattern on the full correct scale, select “actual size” or “set scaling to 100%” or“turn off scaling” in the print settings. Start by printing the first page of the pattern (page 22 of the pdf) and measure the test square to check it is exactly 1” x 1” (25mm x 25mm). Cut off the borders of the pattern pages as needed and match the numbered/lettered triangles and tape the pattern together. A 3/8” seam allowance (1cm) is included.
MATERIALS
  • Jersey knit fabrics with 25% stretch (lycra or elastane):
    • 0.5 meter/yard for sizes 62 – 92 | 0-3M – 18-24M
    • 0,75 meter/yard for sizes 98 – 116 | 2-3Y – 5-6M      
  • Fusible interfacing for the front closure
  • Thread
  • Ballpoint sewing needle
  • 3-4 (snap) buttons
  • pins
  • scissors
  • Sewing machine / Serger
  • Pattern & Tutorial
A FEW THINGS ON SEWING KNITS
 
A serger is ideal for finishing knits – it automatically makes a stretchable finished seam. But if you don’t have a serger you can substitute the serged seams with a knit stitch or small zigzag stitch on your sewing machine. When using a sewing machine, always start with a double layered test swatch to try to find the perfect stitch setting for your selected fabric. For the main seams use a knit stitch or a narrow zigzag stitch. When using a zigzag, start by setting the width and length very low. Make a row of stitches on your test swatch and give it a gentle pull. If the thread breaks, the seam is not giving enough tolerance for the fabric to stretch. Adjust the length of the stitch (bigger means more stretch). You can also try and lower the tension of the upper thread. 
Okay, let’s get started! Cut out the pattern pieces.
Start with the two bib pattern pieces. Fuse the interfacing to the wrong side of the fabric. With the right sides together, fold both bib sides in halve and close the curved neckline seam with a knit stitch or a small zigzag. Grade the seam, turn & press the neckline. Overlap both bib sides between the notches and pin down.
With the right sides together, pin the bib to the front, and close the seam in a knit stitch or a small zigzag. Cut a notch towards the beginning and end of the seam.
With the notch as your turning point, start turning the bib side seam of the front pattern towards the side seam of the bib. The notch gives you the space to make the turn.
Pin the side seams together.
Make sure you have a good view of the beginning of the previous seam. That’s your sewing starting point. Place the needle of your sewing machine exactly where you started the previous seam. Close the seam with a knit stitch or a small zigzag. Repeat steps 4 – 6 for the other side of the bib.
Finish the seams of the bib with a serger or use a big zigzag stitch. Press the seam down. Admire your work, this was the hard part!
Take both yoke parts in the main and lining fabric. Pin with the right sides together and close the neck seam. Grade the neck seam, turn & press the neck seam. Pin the yoke to the front of the shirt and stitch with a knit stitch or a small zigzag. Clip the corners of the seam allowance at the neck line and finish the seam with a serger or a big zigzag. Press the seams towards the back.
Topstitch the shoulder seam.
With the right sides together, pin the back yoke to the back pattern piece. Close the seam in a knit stitch or a small zigzag. Finish the raw edge of the seam with a serger or a big zigzag. Place the front and back flat with the right side up. Start pinning the sleeve to the shoulder area by matching the sleeve cap notch to the shoulder notch.
Pin the sleeve down and serge together. Sewing machine: use a knit stitch or small zigzag stitch and finish the raw edge with a big zigzag.
Finish the raw edge of the sleeve hems and the bottom hem of the shirt. Line up the raw edges of the side seams with the right sides of the fabric together. Serge the seams together from wrist to hem. Sewing machine: use a knit stitch or small zigzag stitch and finish the raw edge with a big zigzag.
Fold both sleeve hems and bottom hem up towards the inside 2,5 cm (1”) and zigzag stitch across the top to hem.
You’re finished!!!