Assalamu Alaikum
Not sure where you're living, but if you are in the US, there are stores like kohl's, burlington coat factory, or any other department stores that sell cotton scarves that can be worn as a hijab..they're usually in the purse section of the store.
As for wrapping the hijaab, here's what I do..
1. If your hair is long, tie your hair in a low bun/ponytail, make sure your hair is secure in the front and the back.
2. Since you have an amira hijaab, I'm guessing it's 2 pieces, right? Put the smaller piece on, and if it's loose a little bit, you can use a large safety pin or hair tie to tighten it from the back.
3. Take the cotton hijaab or your long hijaab and secure it under your chin with a safety pin, then pull it back so it's tight around your head and it's not protruding from the front. You should have one long side and one short side of the hijaab now dangling on each shoulder.
4. Take the long side and continue wrapping it around your head slowly making sure you straighten it out as you go around..once you can't wrap it around anymore, secure a pin on the side.
5. If it's not covering your chest properly, just pull the part that's wrapped around your neck and adjust it.
That should be it
When I wore hijaab, it took me a few times to get it 100% right..just practice in front of the mirror a few times when you're not busy, and you'll be able to get the hang of it. Everyone's head is shaped differently too, so maybe one way may not work as well for you as it would work for someone else. There are also hijaab websites that sell nice hijaabs, if you need any of those sites, let me know.
As for wearing long sleeves, why not try wearing a abayah? You could also wear nice sweaters or long cardigans. When the fall and winter seasons begin, just stock up on long sleeves since that is usually when they are sold..and when those seasons are almost over, they usually go on sale for really cheap if you are tight on money. So be on the look out for those types of sales. There's also islamic clothing online shops like
http://www.shukrclothing.com/international/middleeast.aspx?sh_nrdr=1 which caters to muslimahs.
Let me know if none of what I said helped, I'll try to help as much as I can inshallah.
fi aman Allah
w'salaam
