Candidates preparing for the UPSC can use various strategies to memorize facts effectively. Techniques such as mind mapping, spaced repetition, and active recall can be beneficial. Creating visual aids like charts and flashcards can also enhance retention. Daily revisions and incorporating mnemonics can help in recalling important facts. Additionally, discussing complex topics with peers and teaching them can reinforce understanding and memory. Lastly, breaking down information into manageable sections and setting realistic goals will facilitate a structured learning process.