Start with memorizing one ついたち. 2-10 end with か. 2-5 uses a small or big つ in the middle. After knowing 4 よっか double/lengthen it to 8 to make ようか. 7th and the 9th begins similar to the number 7 and 9 just add の in the middle. 6 is むいか. For the finish I think of full for 10 とおか.