The five R techniques for writing summaries: Read, Reduce, Record, Review and Rewrite:

The five R's stand for Read, Reduce, Record, Review and Rewrite. 

1. Read: Going through passage thoroughly for getting it properly. We may have to repeatreading a couple of times depending upon the degree of complexity of the text. 
2. Reduce: Without adding our own ideas, we need to note down all the relevant and important ideas avoiding the less important. 
3. Record: Draft preparation from the notes, one's own words can be used. Though not forbidden, not advisable to copy sentences or phrases directly from the original. Proper order and coherence be maintained in the draft. 
4. Review: After the draft is prepared, we have to go through it very thoroughly. While reading, check the main points and include them if left, check the irrelevant point and avoid them if found, check the coherence and maintain it, check grammatical or lexical mistakes and correct them, and check the meaning of the draft compared with the original. 
5. Rewrite: Rewrite it neatly from the corrected draft and try to limit it to the one third length.

Also Read: What is paraphrasing?

Also Read: What is Precis?

Also Read: What is summary?