Matthew F.
Start with only five. Do that for five days in a row. Then bump it up to six. Do that for five days in a row. Repeat the process, adding one push up to the count every five days. If five days is not enough time for your body to acclimate to the extra push up, then add in extra days. The goal here is slow and steady gradual practice, so by the time you do ten or more in a row, your body is ready for it.
Dr O.
You can always start with easier variations of push ups and then work your way up to the classic.
1. Push up on the wall
2. Push up on a chair or step
3. Lay down push up
4. Push up on knees
5. Classic push up