Begin practicing writing letters or numerals by looking at cards posted on the wall standing about 5 feet away, tracing the shape in the air with fingers extended. These cards can be made easily, the first part of the letter is purple and they know to begin with this part followed by the last part of the letter, which is drawn in green. After they had traced in the air a few times, then have them trace the letter in in the palm of their other hand. Have them hold up their hands high enough so that if they raise their eyes slightly, they can see the large letter card just over their hands.
"...learning of the alphabet should be made a means of cultivating the child's observation: he should be made to see what he looks at. Make big B in the air, and let him name it; then let him make round O, and crooked S, and T for Tommy, and you name the letters as the little finger forms them with unsteady strokes in the air. To make the small letters thus from memory is a work of more art, and requires more careful observation on the child's part." -Charlotte Mason, Home Education, vol 1 pg 201It can be most pleasurable to use a sand tray to write letters or numerals. If they had trouble such as making the letters or numerals backwards, they could trace them in the air as we had done before, and then go to the sand tray immediately.
"A tray of sand is useful at this stage. The child draws his finger boldly through the sand, and then puts a back to his D; and behold, his first essay in making a straight line and a curve."
Use frosting in tubes on graham crackers!
Write with fingerpaint on waxed paper. The waxed paper is translucent enough that you can slide a paper with writing guides under it for those still working on correct formation. If you do not have any fingerpaint you can make some with laundry starch and food coloring. It made a very runny fingerpaint that tended to bead up on the waxed paper, but worked fine for practicing writing in a new way. If you have any leftover paint out for free-play painting after formal lessons.
You can use any time of cookie dough for rolled cookies or you can add extra flour to regular cookie dough to make it stiff. Have them roll it into snakes and form them into letters or numerals. I found this great icing made specifically for cookies in squeeze tubes at the store. The instructions on the icing say for you to knead the tube for 1 minute before snipping off the end of the tube. This kneading is great for strengthening finger muscles! After the cookies have baked and cooled have them trace the letters or numerals with the icing. Yum!
I know this looks like I am just trying to introduce my poor homeschooled kids, who have never eaten in a cafeteria, what cafeteria food looks like, but actually they are practicing making numerals in the pudding. We still have a lot of reversals, so we need extra practice with making numerals and what can be more fun than doing handwriting in a hands-on messy way, and then get to eat chocolate pudding afterwards!