Aliasing Issues

Greetings,

I've been working on a pirate-themed design and I've pretty much got it finished. But I was told that it has a lot of problems with aliasing so I've been trying my best to clear up these problems. But unfortunately I haven't had any luck. I've even searched the 'net for some guides but I haven't found any as of yet...

I'm not all that experienced with Photoshop so I don't know how exactly to clear up the aliasing problems. I've tried what some people have suggested but I haven't been able to get the same results. Perhaps I'm just doing something wrong.
I've tried everything else I can think of as well, but it really doesn't make any difference. Either the image remains with aliasing problems or I just make matters worse.
(At one point someone did try to correct the issues for me, but the outlines ended up coming out so bad that I'd have to remake the image all over again, and no doubt end up right back where I started.)

So I thought I might ask here and perhaps someone here knows more about what I could do to clear up these problems. This is my image (which will be resized to 256x256 later on). I can see the aliasing issues, but I can't for the life of me figure out how to fix them. Would, by chance, anyone here be willing to help me with these aliasing issues? Guide me through it, show me what to do, clear them up, or something? Any help at all would be very much appreciated.

Also, in case it would help anyone pinpoint the problem by looking at the original .PSD file with layers, I put it up here. I don't know if it will make any difference, but I figured it was better to be safe.

Thank you for your time.

Guess I'm striking out here too.
Alrighty than, guess I'll keep looking. >>;;