At the beginning of four, my son had nearly no letter or number recognition at all.
I decided to do us both a favor-- I decided NOT to worry about it.
Kids get interested in learning this stuff when they do. Until there's interest, you can do a perfectly great job of frustrating yourself and your child with trying to teach them.
As a preschool teacher, I know my best ally is keeping it playful. What I did with my son was to play counting games (any game which involved counting spaces/dice dots), 'write' lots of thank yous and notes to friends and neighbors (for gifts or just because) and helping him sign his name, having him sit with me and dictate those notes. It helped to take a walk and count how many steps we took or to ask "what do you think that sign says?" (usually a simple, common sign like 'stop') or to count how many of a certain color car or other item we saw (bikes, dogs, cats, etc.) Sometimes, it was fun to pick one number and one letter, write them both down on an index card and go on a 'hunt' for them. Read off addresses of houses as you pass (just as clear numbers: "2012" would be read as "two-zero-one-two"). We used a measuring tape and sidewalk chalk and then measured out the lengths of dinosaurs along the sidewalk, adding a neighborhood invitation ("How long was an apatosaurus?" written next to it-- it will get some interest.)
With letters, I chose to focus on just helping my son learn the letters of his name first. We had sung the ABC song a jillion times, for everything. (It was even a way of timing things-- "I'm going to sing ABCs three times, and then we are leaving the park", etc.) You can make them out of playdough. You can make letters with your bodies. Read a lot together, esp. some good alphabet books. Point to the letters as you say them.
Let her lead. Let her see you reading, counting, too. Here's the thing-- I didn't worry about my son, and he's now five and has grown a lot over the last year. He's come to notice the letters which begin his friend's names at school (they had namecards). He can write his name on the letters and Valentines we sent out. He sometimes likes to make signs-- one day I was making lunch and he seemed bored, so I asked him to make a sign for our 'menu' and spelled out letters to him ('tuna for lunch').
Best of all, playing is still the best way to learn. Keep it fun. If kiddo becomes disinterested after a couple of minutes, follow her cue and find something else to do. I think too many parents forget how a child's brain develops and try to force it at this age. (No thanks to Race to the Top and No Child Left Behind, age-inappropriate educational standards are being imposed on our youngest learners... their brains do not work the way bureaucrats propose...sigh.) To me, the worst thing we can do is to frustrate our children on letters and numbers and learning early on. So keep it simple, keep it light and you will find that she learns plenty in the coming year. 4 to 5 is a huge opportunity for growth, so keep the tv and media (including computer games) at a minimum-- there's so much we know about children's learning which tells us that three-dimensional hands-on experiential learning is still the best for this age.
Have fun with it and she will too.