This is the fun part of designing your plush: What will it look like?
Some things that I keep in mind when modeling for plush patterns:
Keep your topology (mostly) clean! No N-gons!
The straighter your edges, the cleaner your seams.
Keep your model low-poly.
If your plush is symmetrical, use the Mirror Modifier.
Model separate pieces and join them using the Boolean Modifier.
Retopo your model if needed afterwards.
Add your seams!
Once you have a uniform mesh, it's time to cut out the pattern pieces!
Select your model and enter edit mode.
Select Edge Select Mode and Shift + click edges you want to 'cut'.
Once selected, right click and select 'Mark Seams'
Go around your model and start adding seams.
If you can, look at existing plushies as reference! Where are the seams and why?
To preserve the roundness of some areas, look into adding some darts.
Test it out!
Now it is time to test your seams! Do they work?
In object mode, select your mesh.
Head to 'Object' in the top left, and find the Seams to Sewing Pattern menu.
Select the button to convert your mesh to a sewing pattern!
Before pressing enter, set your triangle limit. The bigger the plush, the more triangles you will need (10000 is a good number in my experience).
Once it finished the conversion, check that the seams create an 'accurate' recreation of your model. In the same dropdown, click 'quick cloth sim' this time.
Once the simulation is finished, press the spacebar to preview your creation. Compare it to your original model and make note on what works and what needs changes.
You can either change a seam or change your model's shape, but keep making changes to the model until the cloth simulation is to your liking.
Once you are happy, go back to the seams to sewing pattern dropdown, and select 'Export .SVG'.
