Can anyone explain how to earn 1000 carnival shards without breaking the bank?

Thank everyone for providing valuable suggestions.

I have done all that with winter event and TOTY events, I acquired the cards I wanted with ease.

But this weird event is short and cards are rare and expensive, ex. the cheapest 98OVR card is near 100M. this is not a playable event. EA should stop coming up with this kind of garbage.