6 months?
Mate, I had a Science background as well. I initially planned to study medicine, but then after a complex series of thoughts, I switched to Commerce. And then thought to myself, what better than Chartered Accountancy?
I started preparing for CPT in April, without coaching, and sat for the June examinations.
I scored a 160. Attempted 170.
And. I was a Biology student, so I didn't know much about Mathematics either.
My strategy. I left out Quantitative Aptitude altogether. Only studied a bit for it.
Pay the most amount of attention in Accounts, then Economics and then finally Law.
But remember Law is often the highest-scoring subject, followed by Accounts then Economics.
For Accounts, I used P.C. Tulsian + ICAI Module.
For Economics, I used Padhuka + ICAI Module.
For Law, I used Padhuka + ICAI Module.
And remember. You MUST go through the Scanner and Model Test Papers at least twice before you sit for the exams. The question paper is often repetitive(think of it, that is why they don't let you take away the examination paper :P)
Practice more, study less. That's about it. Study through the mistakes you make when you're practicing.
I'm sure you'll be able to do it. It's not as hard as people make it out to be. Sure it requires a decent amount of effort, but the examination's not god-like. The passing rates are also quite high. Around 35% of the students sitting for CPT pass it.
So quit worrying, and start studying. You'll be on your way to IPCC in no time.
Good luck.
Sam