By far, personal/reflectice essays as the easiest to do. Marking criteria is very strict for short stories/imaginative pieces so i definitely reccomend personal reflective.
Remember:
The examiner is not going to question your personal essay, as in, did that actually happen? Make it up if you need to!
Have you ever lost a loved one? <-- If you have, write about how this person inspired you, how you loved them so much, talk about your feelings before they died, during the time when they died, and how you feel now.
The above example applys to any personal reflectice essay.
Make a Statement:
I never was too fond of roller-coasters, but i was about to face my biggest fear....
Feelings during it:
...As it swerved from corner to corner, my stomach was turning faster than the wheels of a ferrari.
Evaluate: [and how you feel now]
....It really was a traumatic experience, i never thought i would bring myself to go on it. Now after experiencing it though, the shear enjoyment i gained would probably lure me into another go the next time i come across a roller-coaster.
It is vital that you make use of several techniques to show your feelings etc, like similie,methaphor, onomatopoeia,imagery.
Example:
It was frightening. His hair stood tall and his eyes were wide open. He looked like a crazy scientist who had just blown something up in their face.
What i said above is an example of how you could describe what someone looked like; i said " scientist....blown something up in their face ". That statement alone could create an image of someone very shell shocked and it could add humour.
Be inventive when showing your thoughts/feelings/opinions.
I hope i have helped to some extent...