Interview Questions at ISSB generally have four categories:

1. Questions from your personal life
Be prepared for the questions from your personal life specially any troubled times that you might have seen. They give you forms to fill on the first day having questions about whole your life. They know your brought up and any hard times you might have seen or they even rightly predict them without mentioning. Like in my interview I was asked why my academic graph dropped in second year result when I have got good percentage before and maintained it afterwards. Do not panic to answer such questions. Be open and explain each and everything they ask. This way you let them know that you have nothing to hide or feel ashamed of.

2. Questions from GK
Give Geography a special consideration. Like where a country, lake, ocean etc is located. Consult world map as well as that of Pakistan. They may also ask you about roads, currencies and capitals.
Some questions are particular to Pakistan and a few about Islam.
From Current Affairs they may ask about your opinion about particular issues as well as they ask questions about abbreviations like NADRA, PEMRA etc.


3. Academic
There are some questions specific to your field.


4. Mathematical
Since they have your IQ level from verbal and nonverbal tests such questions are to check whether you can apply your mind in practical situations. At first the questions might sound difficult but it is almost never the case.
Make sure you apply the BODMAS rule like: two plus two divided by two is 3 never two. Two plus two into two is 6 never eight. Divide, Multiply, Add and then subtract.

Then there are questions for decimal calculations. Do not panic if they sound difficult at first. They just involve simple consideration. Like 0.5/0.05 equals 10, 0.5/0.25 equals 2. Practice them at your own so you can just pick that up there.

In start they ask simple questions but level of difficulty increases as you answer them rightly. So they may ask some calculations like if one kilogram sugar in of 37.5 what will be the price of 5 kilogram? Obviously you have to multiply but you are not provided with any paper. You can add 30 five times, then 7 and then .5 in your mind if it is easy for you or you can multiply them by visualizing the whole figure in your mind.

Last but not the least
Never never lose your temper be very calm. They usually check your temper in personal questions like by taunting any of your close relatives, by asking what would you do in some particular situation etc.