After years of making stitched leaves, here's what I wish someone had told me at the start. Pad your wire first. I used to stitch the outline wire straight onto the fabric and it always looked flat and stiff. Now I couch a slightly thicker wire along the midrib and thinner ones off the veins, and the whole leaf gains a natural arch once you cut it free. Slip the wire under a few stitches rather than piercing through it, or it snaps later when you bend the leaf. For the veins, split stitch works better than stem stitch at this scale, two strands max. Build the vein color in layers and let the edges get ragged on purpose. Real leaves are never symmetrical, so I trace mine from actual specimens and keep every wobble.
Dyeing comes last, always. Work diluted dye into the fabric with a small brush instead of dipping, starting from the edges inward. The center stays lighter and you get that faded, weathered look without muddying your thread colors. Let it dry flat on paper towel, never hanging, or the dye pools and you get streaks you can't fix. Each one comes out a little diffrent even with the same steps, which is honestly the best part.