Many use to choose optional depends on how upsc asks questions(trend-based optional selection),if they are asking continuously easy ,then one will fall for that subject ,by hearing someone(as they behave like gurubaba) advice or by their own.These are main don'ts while choosing optional Ok let me say ,how the optional can be chosen ,hahha here i am not going to "my subject opinion" or "my analysis of different optional" ,as it will be suitable only for me ,but iam going to show the best way, by urself to find the optional ,which "SUITS U".     >>1.Choose ur optional based on "ur own interest .eg- if u are interested to know more about international relationship ,then take PSIR ;>>2.The optional u choose should be like whenever u feel stressed , it should be read ,so that u may get rid of stress,destress ( sounds astonishing right ,but practicality it will be ,as many are there ,when are in stress ,they usually read some books ,to get rid of,which they get satisfaction of acquiring some useful things u like ,knowledge u wish etc;>>3. Depends on ur own strength and weakness,analyse urself , yes when took the optional eg: If u take public administration ,see ur weakness and strength in it ,if ur strength wins over it then go for it.For this if u found ur interested subject ,then u have to analyse ur strength and weakness in it ,then u have to go for it. Read the syllabus for it ,to know what is what,how u can proceed further.who know u may also read the exact syllabus ,u studied in college ,which will turn out to be ur strength .But if ur college subject is not ur strength ,then vice versa .;>>4.That "eagerness to study" , u should have that much eager to study , u should think of that subject only ,when ever u want give more on ,no other thoughts should ,get into ur mind while doing that,like when u get urself drowned in water ,u will think about only breathing ,that much eagerness to breathe should be there in ur subject . U should breathe ur eagerness to do that subject .These all the main things that u should keep in mind ,while choosing optional .Here I had guided "U to be URSELF" , don't forget the decision is urs.

All this what I said are converted like,
OWN INTEREST +DESTRESS + ANALYSIS OF URSELF +EAGERNESS = FAVOURITE SUBJECT .

I wish UPSC to change the name from "OPTIONAL SUBJECT" TO "FAVOURITE SUBJECT" ,which the best suits it . As students also will be very much aware ,while choosing optinal.
Haha who knows this post may turn into proposal by UPSC in future.So if u choose ur FAVOURITE SUBJECT ,Named as optional like this means, I AM  SURE ,EVEN U WILL GIVE TOUGH TO UPSC , WHATEVER TOUGH PAPER IT SETS For sure u will crack the exam,no matter what is ur age,what stage u are,what condition u go through , don't forget that every five fingers are not same , as every one will not be in same situation to face , but its "U decide the biggest power is U" , who can change the "crisis into opportunity", "Tragedy into Victory"Its all u , ur attitude will do., if u need any mentorship advice ask me ."BELIEVE IN U". BEST OF LUCK ALL,MEET U IN LBSNAA

With wishes and regards

Vinoth kumar.M