I am a final year undergraduate and have $30000 of spare savings. What should I do with this sum of money to receive the best return in say, 5-10years?

Your horizon is long enough to take on quite abit of risk. I would suggest a super-concentrated portfolio of 3 companies that you feel will do well in 10 years.

1. Pay off all loans that is above 4%
2. Put the extras that u have in cpf special/medical account that yields 4% risk free.