Need advice on creating a 5-day push-up and crunches exercise

Hey everyone!

I am preparing for a PT test involving push-ups and crunches. My current max in *good form* for push-ups is 11 and crunches is 9. Pretty terrible, I believe. I am in my mid 20s and lead a pretty sedentary office job.

Anyways, the large majority of people recommend training push-ups & crunches every hour or so, and this way you'd be doing hundreds and quickly be able to gain lots of reps. However, in my case and the reason I came here, is to ask if it's possible to still increase your reps (in a somewhat efficient way) while still only having around 30 mins available to train daily.

I'm sorry if this has been asked before but I am unable to find anything. Would a routine of 5 days a week be optimal, or would it be best to train one day, rest the next, train the next, etc?

Many thanks!