In case you are curious about the "make-it-up-as-I-go-along" method sometimes used in my construction, I'll walk you through the process:
So here is the photo I showed at the bottom of this post. This is my blank slate. Use whatever basic tee shirt pattern fits you. After you put the shirt together, try it on and, using a mirror, stick pins where you want the neckline to be. If you look closely, you can see my pins in the photo above. It's going to be a V-neck henley.
Here are the pins again. I'm checking the length of the button-area with my buttons. No measuring here!
Measure to make sure the pins are spaced equally from each armhole/side seam.
Cut with reckless abandon by the pins!! Make sure to leave a seam allowance around the neck edge. The button part is just a slit. If you wanted to, you could draw the neckline with disappearing ink or chalk first.
Measure around the neckline to see how long the neckband/button band needs to be. Cut the actual neckband a couple inches shorter than the measurement and stretch it around the neck edge so it will hug the neck instead of sticking up. The width of this piece is 2x the desired finished neckband width + 2x the seam allowance.
My neckband is 1.5" and my seam allowance is .5", so my neckband piece was 4" wide.
Next, stabilize the neckline where you will stitch. I haven't done this often before, but I will definitely do it in the future. This pre-cut strip was easy to iron on, too. No worries about stretching out the neckline. I just wish I'd used a bigger piece (instead of the strip) at the bottom of the slit before I cut it.
Stitch the neckband/button band piece to the neckline and slit edge.
This is a little tricky for me to explain: Wrap the neckband/button band around itself and to the back, making sure the finished front is an even width (my band is 1.5" wide). Pin and stitch in the ditch on the right side between the body and neckband/button band to secure the band on the wrong side. Trim the excess on the wrong side.
Stitch the bottoms of the button band sections to the bottom of the slit (another hard part for me to explain - should have taken a pic of the process). This is where I wish I had more zealously interfaced the bottom of the slit. You can see it's a bit stretched out on the right. I was able to press this mostly out (and let's not forget it's a pajama shirt!), but it's not perfect. :-(
Add button holes and buttons (sorry, no pic)
And, voila! The finished product.
Since this is a jamie shirt, I wanted it to be really comfy. If I were to make this for daywear, I'd interface that button band. The fabric I used is bamboo/cotton interlock from Fabric.com - sooooooo soft and snuggly. I may need more in the future to make a whole pajama set including comfy pants or shorts.