You can pay the fees of KCET application form through E-challan or DD. There is no online fee payment option. 

You can check the details below

Bank Challan - Candidates have to download the bank challan after selecting their bank. Candidates have to pay KCET 2018 application fee at branches of State Bank of Hyderabad, State Bank of Mysore, Indian Bank or e-Post Offices.

Demand Draft - Candidates from outside India have to pay the application fee of Karnataka CET 2018 through Demand Draft (DD) drawn in favour of "Executive Director, Karnataka Examinations Authority", payable at Bangalore.

Good Luck!!