Make sure you score very well in Physics, Chemistry and Mathematics papers of PU board exams because half of the weight-age while considering a rank is given to board score, It will affect a lot in a long run and is crucial for your rank.

Now for KCET, be thorough with NCERT for Chemistry. Do exemplar ,NCERT text book and one JEE Main book for mathematics. For Physics , better do a JEE mains book like HCV along with NCERT.

Most important part is previous papers. Give mock tests for both boards and KCET based exams, most questions appear as it is from previous papers. So better do not miss these.

All the best..