How do I fit more on my resume without cramming?

Fit more by editing, not by squeezing. The most effective ways are:

• Merge similar bullets: two bullets about reports become one stronger bullet.
• Cut filler words such as "responsible for", "various" or "duties included".
• Turn long lists of tasks into one result-focused line.
• Reduce older roles to a title, company, dates and one line.
• Group skills on a few lines instead of a long vertical list.

Example: Instead of "Responsible for preparing weekly sales reports for management review", write "Prepared weekly sales reports for senior management."

Then fine-tune layout slightly: margins around 1.5 to 2 cm and body text at 10 to 11 points. If it still does not fit, a second page is acceptable for experienced candidates.