dear student

first of all go through the entire syllabus for the CLAT 2019 examination and exam pattern so that you can do effective prepation.

Give mocks to know your current the level of preparation. You will come to know about your strong and weak areas and then strategise accordingly

you can reger WORD POWER MADE EASY by Norman lewis to improve your vocabulary

for logical reasoning and QUANTATIVE APTITUDEby solve RS Agarwal 

for current affair start reading newspaper. I would recommend to read tHE HINDU newspaper. It is the most useful and important part is editorial part for improving english as well as current affairs.

there are many online study material you can find online. You can go with the CLAT tutorial of Opus Way.

https://www.theopusway.com/

hope this helps

All the best!!!