How to Tailor a Men's Dress Shirt to a Slim Fit

I have darling sons who happen to be very fit & slim. They get it from me I guess their dad has something to do with that. Anywho, they love the new fitted dress shirts. Christian is required to wear a uniform shirt at work that is made for more of a middle aged, muffin top mature man. It fit him in the collar & in the length of the sleeves, but that was it. His work shirts were driving him nuts, so he turned to The Sewing Queen {hey, if I can't be a Disney princess, it works for me!}. 

Here's how I took in his shirt: 

Disclaimer: If you're thinking, "Holy cow - those are the worst tutorial pictures I've ever seen. The shirt looks a different color in every shot! Is it even the same shirt?! Um, I would have to agree with you. This was one of those late night projects where I was my own photographer in terrible lighting. So sorry! {Note to self: up your game!}

Step 1: USUALLY while sewing garments, the right sides of the fabric are put together. But I used French seams, so I started with the shirt right side out & pinned the wrong sides of the fabric together along the existing side seams of the shirt, under the arm & along the bottom seam of the sleeve.

Step 2: I sewed the wrong sides together. This shirt was way too big, so I think I sewed about an inch seam on the sides & brought it in a little more narrow on the sleeve.

Step 3: Trim the seam from step 2 pretty closely.

Step 4: Press the seam open, then fold the shirt on the seam & press. {Now the shirt is inside out.}

Step 5: Pin & sew again with the right sides of the fabric together. Here I sewed about a 3/8" seam. 

Step 6: Press seam open. Photo number 6 represents what the seam looks like on the inside of the shirt. As you can see, the beauty of French seams is that there are  no raw edges!

Step 7: {You can skip this step if you like.} Sew the French seam down. But I wouldn't recommend trying to do this in the sleeve. Just stop at the armpit. 

I don't have a "Before" photo, but here's the "After" & it fits his slim body much better!