If you made clothing in blender (or another 3d program) you can import it into Marvelous Designer, and export it as .SAMD
First you export it as a .OBJ
Then you go to Marvelous designer and import it as "Obj to garment"
Make sure you have "Trace 2D Pattern from UV map" activated and for scale either use "m" (meter) or "auto scale".
Now your obj is a garment and can be simulated. Usually you will notice when you simulate your garment that not all the pieces are sewn right to each other.
So you have to fix that by moving the sewing lines, or removing the sewing lines and some dots to sow it back together.
Here how you can move your sewing lines. First select: 'Edit Sewing (B)"
Now you can see where the problem areas are, and you can push and pull on the sewing lines to move them to the right place.
Until they are on the right position
But sometimes it is better to remove the sewing lines first. So with still 'Edit Sewing (B)" selected you can right click on your mouse button to select the sewing line you wish to remove. And you will get a menu popping up. There you choose "remove sewing"
And after you removed the sewing lines you will remove the dots that are not needed for your design. To do that you will first have to activate the right tool to do that; "Edit Pattern (Z)"
Then just click a dot with your right mouse button to get the menu and choose: "Convert to curve point'.
And repeat this step until all the unwanted dots are removed.
Then it is time to sow your garment back together. Now you can click on the tool "Segment Sewing (N)".
When they are all done, you can run the simulation again to check if all is right now.
When you are satisfied with your work, just export is as .SAMD so you can load it up to Sansar.
And here the result. Van .obj to .samd