A-B = full length + 1/4 inch
A-C = 1/4 chest + 1/2 inch
Square out lines from points A, B, and C.
A-F = half shoulder + 1/4 inch
C-H = 1/4 chest + 1 1/2 inches (Note: This 1 1/2 inches is the ease. If you think this is more than you prefer, you can reduce the ease to 3/4 inch. If you prefer to use a knit fabric or any kind of stretchy fabric, there's is no need to have ease, as the fabric itself is stretchy, or an ease of 1/2 inch is enough.)
B-K = 1/4 chest + 3 to 4 inches for kids' size (1/4 chest + 6 to 8 inches for women's size) (You can increase this measurement according to how wider you want your hemline to be.)
A-D = 1/12 chest + 1/4 inch (You can change the width of the neck according to your preference.)
A-E = 1/12 chest + 1/2 inch (You can change the depth of the front neck according to your preference.)
Shape neck D-E.
Square down from F. Mark I where the squared line crosses H-C. Mark M where the squared line crosses B-K.
F-G = 1/2 inch (1 inch for adult-size dress)
Join G-D.
I-J = 1 inch
Shape armhole G-J-H.
L-K = 3/4 inch (1 inch for women's size)
Shape bottom hemline B-M-L as shown.
Extend B-M-L 1 inch for bottom hemline fold (shown by a dotted line in the pattern).
Back:
A-B = full length + 1/4 inch
A-C = 1/4 chest + 1/2 inch
Square lines from points A, B, and C.
A-F = half shoulder + 1/4 inch
C-H = 1/4 chest + 1 1/2 inches (Note: This 1 1/2 inches is the ease. If you think this is more than you prefer, you can reduce the ease to 3/4 inch. If are going to use a knit fabric or any kind of stretchy fabric, there's is no need to have ease, as the fabric itself is stretchy, or an ease of 1/2 inch is enough.)
B-K = 1/4 chest + 3 to 4 inches for kids' size(1/4 chest + 6 to 8 inches for women's size) (You can increase this measurement according to how wider you want your hemline to be.)
A-D = 1/12 chest + 1/4 inch (You can change the width of the neck according to your preference.)
A-E = 1 inch (You can change the depth of the back neck according to your preference. )
Shape neck D-E.
Square down from F. Mark I where the squared line crosses H-C. Mark M where the squared line crosses B-K.
F-G = 1/2 inch to 3/4 inch for kids (1 inch for ladies)
Join G-D.
I-J = 2 1/2 inches
Shape armhole G-J-H.
L-K = 3/4 inch (1 inch for women's size)
Shape bottom hemline B-M-L as shown.
Extend B-M-L 1 inch for bottom hemline fold (shown by a dotted line in the pattern).
E-N = C-P = B-O = 1.25 inches. Join N-P-O for button and buttonhole extensions at the center back. Cut the back pattern at N-P-O for full opening.
You can also cut out the button placket (2.75-inch width) from another piece of fabric and attach it to ECB. In that case, you have to add a seam allowance of 0.25 inch at ECB.
Seam allowances to be added to this dress are 0.5 inches at the neck, shoulder, and armhole, and 1 inch on the sides. The hemline allowance (1 inch) is already added in the pattern draft itself.
I have posted a free A-line dress sewing pattern for kids' sizes 6 to 12 years at this link and for sizes 3 to 5 years at this link. Hope you may find it helpful.
You can find lots of free PDF printable sewing patterns on this page on my blog.
You can also click the Free Sewing Patterns Page at the top of this blog page (under the blog title) to find more free sewing patterns.
Click the below links to have a browse through the pattern drafting and sewing tutorials on my blog.
Please check the below links to see the tutorial for making this dress: