Okay, a sleeved wrap dress is a difficult one to grade if you don't understand grading fully & neither 1/2 inch around & cutting through the middle, is going to be entirely accurate & will affect the fit of the dress - I've known plenty of experienced pattern cutters & even a fashion university lecturer who couldn't even begin to do it
its also a difficult 1 to explain without visuals, so I think the best I can do is list the grading increments & WHERE the extra needs to be added & hope that as you can sew, maybe you can work it out from there.
Okay .......
Bust - total increase 2"
(split between number of panels & allow for wrap)
Waist - 2" (as above)
Hip - 2" (as above)
Across back - 1/2" (midway between shoulder/armhole)
Across front - 1/2" (as above)
(note - as its a wrap you will need to adjust neck shape at wrap edge, to compensate or notches wont match)
across sleeve head - 1/2"
(note that X back + X Front & 2 Sleeve heads = 2" same as other round body increments)
Shoulder increase - 1/8"
Armhole front - 3/8"
Armhole back - 3/8" (3/4" total armhole)
(note - your sleeve head also must grow by 3/4" - but this should be spread through total armhole shape - 1/8" (x2) at each side of under arm & 1/2 across upper arm)
through sleeve width - 1/2"
Sleeve length - 1/4"
Neck width & depth should also change, but as its only 1 size you could probably get away with not doing that
You can do this easiest by getting some paper - pattern, wallpaper, newspaper prit-stick or cellotape into larger sheets
- fold paper - pin your folded pattern at centre front along fold - draw around your folded pattern - unpin & move over 1/2" from folded edge & pin again - draw around it again in a different colour -
using increments above as a guide to where the new line needs to be, plot the points at across front/back, a/hole & shoulder & draw in new line in the same colour as outer hip/bust etc line
repeat with sleeve & cut out on fold, but cut out back a/hole shape only - open out - & now trim away front a/hole
Hope thats something you can follow :)
grading the sleeve & armhole area correctly is very important, as it will keep the sleeve fitting comfortably, not doing it will distort it & it will pull & feel/look odd