Basically, a dissertation title informs the reader what to expect of the research; It summarizes the core idea. It underscores the field of study and purpose of the study, from which the readers derive the outcomes and context. A title should be properly framed such that it leads the readers into the research seamlessly avoiding the trouble of confusion. Since writing a thesis, by itself, is a highly disciplined act, there are set guidelines that the title should follow.
DOs
Precise: The title should not be a bubbling mass of indistinct words. The title should be written as laconically as possible, avoiding the possibility of unnecessary words.
Unambiguous: The should be indicative of the core focus of your study; ambiguity might mislead the readers into expecting outcomes that digress from the actual. There must be clarity as opposed to ambiguity.
The title should highlight the purpose, theory, methodology and primary source used.
Capitalization: The first word of the title should be capitalized. Articles, prepositions and coordinating conjunctions should not be capitalized.
Don't
Do not frame a complete sentence as a title.
No period should feature at the end of the title
Avoid using acronyms and abbreviations. Acronyms and abbreviations tend to possess multiple meanings which may lead to ambiguity.
Informal language should be strictly avoided as it lessens the degree of solemnity of your research.
Do not use quotation marks around the entire title. If need be it, use double quotation marks.
Do not use mathematical symbols.
Every word in your dissertation title adds meanings and directs the thesis in a said manner. Flouting guidelines reflects the paucity of professionalism on one's part.