The sounds of masturbation can vary greatly depending on the individual, their intensity, and the specific act. There's no single "correct" way to write it, but here are some approaches, categorized by intensity and tone:

Low Intensity/Subdued:

• Soft Moans: Use words like "hummed," "murmured," "whispered," "sighing," or "softly groaned." Focus on the breathiness and gentle sounds. Examples: "A soft hum escaped her lips," "She sighed contentedly," "A low murmur vibrated in her throat."
• Internal Sounds: Instead of explicit moans, describe the physical sensations. "A wave of heat pulsed through her," "Her muscles tightened," "A tremor ran through her body." This approach is more suggestive and leaves more to the reader's imagination.

Medium Intensity:

• Building Moans: Start with softer sounds and gradually increase the intensity. Use words like "moaned," "groaned," "whimpered," "gasped." Describe the rhythm and pitch changes. Examples: "A low moan rose in her chest, escalating into a soft groan," "She gasped, a sharp intake of breath followed by a drawn-out moan."
• Varied Sounds: Incorporate other sounds like soft whimpers, sighs, or even the sounds of movement. "Her breath hitched, a soft whimper escaping her lips as she moved," "A low groan punctuated the rhythmic sounds of her body."

High Intensity:

• Intense Moans: Use stronger verbs and more evocative language. Words like "cried out," "screamed," "shrieked," "wailed" can be used, but sparingly to avoid overuse. Focus on the raw emotion. Examples: "A sharp cry escaped her lips," "She screamed, the sound raw and unrestrained," "A wave of pleasure washed over her, a strangled cry escaping her throat."
• Descriptive Language: Don't just say "she moaned." Describe the quality of the moan. Was it breathy, guttural, strained, or ecstatic? Examples: "A guttural moan ripped from her throat," "Her breathy moans were punctuated by sharp gasps," "Ecstatic cries filled the room."
• Physical Manifestations: Describe the physical effects of pleasure. "Her body arched," "Her fingers clenched," "She shuddered violently." These details add realism and intensity.

Tone Considerations:

• Romantic: Focus on tenderness, intimacy, and passion. Use softer sounds and more lyrical language.
• Sensual: Emphasize the physical sensations and the pleasure experienced. Use evocative language and vivid imagery.
• Explicit: Use stronger, more direct language. Be aware of your audience and the context.

Important Note: The key is to use a variety of sounds and descriptions to create a realistic and engaging portrayal. Avoid repetition and overuse of any single word. Show, don't tell. Focus on the emotional and physical experience rather than simply listing sounds. The most effective writing will leave some to the reader's imagination.