For many reasons, that may be one of the harder skins to start out on. It's a first-generation skin, and it has mirror issues and other bugs in how the skin is mapped onto the 3D mesh.
On the other hand, sometimes these skins can be very useful to get you into the right "mindset" -- that is, teach you how to manipulate the pixels more to get what you want.
A few tips:
- Move mouse cursor off the screen when taking screenshots
- The number on the cowling: move it back to avoid the warping on the leading edge. Tweak it. You might have to sacrifice historical accuracy to work on some of these old skins. The real plane may have the number at the very front of the cowling, but on the skin it may be better to move it backwards a tad. There was a time when the 109E had to be mirrored left and right, so I had to make the number on the side "8" instead of "11".
- The star on your port side is irregular and requires tweaking. The leading edge is pushed backwards (into the roundel) and it doesn't look right
- When you work with colors, and where they end or where they meet, you want to alias the demarcation. You can decide how much "blur" it will have, but as-is you have saw-tooth patterns on your nose where the light blue meets the dark blue uppers. Depending on how you do this, you might try using a different tool, or creating a new selection with "alias" eneabled, or just going-over the saw-tooth edge with a brush and/or eraser tool to fix it.
- On older skins like this, they often default to 256x256. Make sure you up-scale it to 1024x1024 before doing any work!!! You will have to redo all the details from scratch, as these old skins never came in hi-res. No template to work off of. All skins must be 1024x1024 for HTC to accept them as submissions, and even if you never plan to submit it, it would still be good to practice in the "full scale"!
Keep at it! I see some areas that need improvement, but it always feels good to get that first skin out of the way.