Start off with your manly box-like shirt and straighten it out.

Make it as perfectly flat and straight as possible :)

Then turn the shirt inside out.

I don't do well with measurements, so I just took some chalk and went ahead with how much I think I should take in.

This fitting the shirt pretty much!
Start with the sleeves, the very tip and then draw the line down to the very bottom, make sure it's even!

Cut away the extra fabric, now you have a fitted shirt :)

To make it even more girly, I suppose I "cuffed" the sleeves, I don't exactly know what to call it.

Anyway, I put elastic at the end of the sleeve and stitched it into place!

Fold the tip of the sleeve over the elastic and sew the elastic into the sleeve.

After you've done that with both sleeves - it should look as pictured.

Cut the elastic band from the neck. This makes the collar less manly.

The product of all the following steps should resemble this.

Measure an inch around the entire neck with chalk.

After you've cut the neck out, it should look like that. This makes the shirt a lot more feminine.

You can stitch around the neck if you like, but I didn't so it would have an edge to it.

You don't have to do this, but I did as an experiment; a risk.

Measure down the back, my mark is 13 inches down from the neck.

Make a bow!

You can use glue or thread, but since I ran out of glue... I used thread.

Not perfect, but close enough.

Then put the bow onto the shirt and stitch it into place.