In Jainism, masturbation is generally seen as a form of sexual indulgence and is not considered helpful for spiritual progress.

Jain view

• It is associated with kāma (sensual desire).
• It can increase attachment to the body and sense pleasures.
• It may strengthen vāsanā and make it harder to develop:

- brahmacharya, - self-control, - vairagya, - and inner purity.

Spiritual effect

From a Jain perspective, any act driven by strong sensual craving can:

• attract pudgala through bondage,
• disturb equanimity,
• and create obstacles on the path of moksha.

For householders

For a shrāvaka / shrāvikā, Jain ethics encourage restraint and moderation. Masturbation is not praised as a virtuous act, because it does not support control of mind and senses.

For monks and nuns

For sadhus and sadhvis, complete celibacy is required. Any sexual act, including masturbation, is a serious breach of brahmacharya.

Jain practical guidance

Jainism would advise:

• meditation,
• pratikraman,
• keeping the mind engaged in dharma,
• reducing sensory triggers,
• and cultivating self-restraint.

If you want, I can also explain this from the Shravak dharma point of view or the monastic point of view in simpler words.