As the NTS announced ....your test (crime scene investigation) will comprise of
English 10 marks
Analytical 10 marks
Computer Sceince/Networking 10 marks
natural sciences 70 marks

English

this portion includes grammatic fill in the blanks (3-4)
vocabulary (2-3)
synonyms/relationships (2-3)
This portion isnt that tough ...you need to aim 10/10 in this
Grammar is mostly of undergraduate level ....you can consult Wren and Martin or Rymond Murphy for this.
Vocabulary you cant prepare in a day or two ....but mostly they ask not so difficult.GRE Word list always help in vocab of any level but it s too extensive that i wouldnt suggest the beginners to memorise them.as they wouldnt ....but the people striving hard for multiple competitive exams i ll suggest aik dfa jaan maar k ye word list memorise kr lain ...it ll help in all the set of exams.

BASIC computer science and networking/Analytical

again difficulty level isnt that high ...comparing to GAT-General ...again aim 20/20
for prep ....one can consult GAT-General book or CSS Aspirants can consult EDS General ability portion.

Sciences

the real part of the test ....comprise generally
Forensic Science
Physics
Chemistry
Toxicology
Zoology
Botany

Forensic Science

questions are generally basic level ...if one prepare ...one can score good ...
U need to focus following
1.Basic definitions,scope,application and sphere
2.Evidence collection nd preservation
3.finger printing
4.DNA Sequencing
only general terminolgies will help you to sail through this ....go through all the introduction of different fields of forensic sceince given on pfsa website ...nd a little net surfing writing basic forensic science can help u prepare ths section.

Physics

interesting and conceptual ....find out your f sc books and revise all the basic concepts.

chemistry

FSc book focussing on ..
1.periodic table along with general trends within different groups
2.Biochemistry

toxicology

search online a list of poisons nd their anti-dotes ....emergency managment of common medical conditions

Botany

1.taxonomy (as much as u can)
2.ecology
3.application ofbotany in forensic science

zoology

largely phylum nd classes
basic physiology

__________________
War does not determine who is right - only who is left.