Use digital text editors
We live in the digital world, where information technology has provided various tools with artificial intelligence to solve our problems. There are many digital text editors available which are equipped with grammar correction and spell check tools. You can use them to highlight the errors and get suggestions. But, tools are tools, they are not perfect. So when you use these tools you need to apply your own understanding of the language and subject before accepting the suggestions offered. Alternatively, you can use the spell check and grammar correction option available in the Pages for iOS and in word for windows operating system. But they have limited options as compared to the other softwares.
Read the document with a fresh mind
You tend to oversee the mistakes and your mind fills in the gaps as you are aware of the concepts and ideas. After you have completed the dissertation, take a break and read it with a fresh mind. You will be able to spot many mistakes that you missed while you were writing.
Read it aloud.
You can spot the mistake when you hear rather than when you read a text. Once you have completed the dissertation, read your dissertation aloud, you will be able to tell where you have missed the punctuations and misspelled.