believe me i didnt buy any book for its preparation....and even if you do no gaurantee that question will be asked from that.what i did was googled few things

1 top 10 architects in world and their works (memorise the names,and their works along with the pictures of their built monuments)

2 top 10 architects in india and their work

3 top 10 historical monuments and its history(they will give picture of different monuments and you should know their name)

4 practise logical reasoning! it is available online for free....(download non verbal and verbal reasoning by rs agrawal )

5 brush up your basic maths formula like that of binomials,probability the chances of both this topics being asked is the highest

6 solve last 15 years papers ! all available online

7 go to youtube watch

do rendering of different objects...take any damn object arrange it in composition and then sketch it

8 if time permits visit historical monuments and try to sketch it. practise perspective drawing as much as possible

9  google the history behind why a specific logo was designed and try create your own logo

10 download flipboard ...have some basic information of ongoings in world ....incease your gk

11 google some 2d compositions...remember basic rule for composition it should be a balanced one and use maximum of 3 colors to color it not more than that