Sewing Lace To Shirt - How Do I Protect Stitches On Wrong-side

there is knit tricot fusible interfacing ( its stretchable and iron glue-able ). Normally, in RTW, if u notice insides, they have some interfacing (mostly similar soft stretchable, unless it is heavy embroidery) to protect threads and damage.
It is inexpensive and can get from amazon. Cut and hot iron it.

Could not find on amazon on joanns:

https://www.joann.com/pellon-easy-k...MIz_Dl4e3A9wIVJBxlCh16UgIwEAQYASABEgIlu_D_BwE
thanks for this post, i also need to buy to keep in stash

 

yes, they are usually washable. But yes overtime with continous washing over years, they might starting peeling out, but should be okay, given how much we wear same top and wash.
I think black would go better with your tee shirt. If you buying bulk, then white might be more usable. With dark navy , it is transparent to show outside, unless thin fabric of tee shirt, which in that case, wont be suitable for embriodary.
So its your call.
Package usually has instructions, hot iron directly or with wet towel.


Tricot Fabric - Tricot Fabric by the Yard | Fabric.com
Sewing 101: Using Tricot Fusible Interfacing

 

it stabilizes the fabric, hides the seams, saves the embroidery threads and knots touch/itching skin, and also saves it from accidental or washing machine mishaps, like getting stuck or pulled in necklace chain.
If you feel your patch/embroidery looks fine, you do not need to add it. No one will know ... Like in Indian garments, you hardly have any patches, and indian garment fabrics are woven/more body and like tshirt, and inside, we wear inner wears (inner tank) mostly anyways.

 

just fYI- at Joanns/Hobby or other big stores if you have in the area ( NYC etc), you may be able to find in limited amounts. I have woven one bought by yardage like 1/2 yards