Paraphrase the meaning, not just the vocabulary
Replacing a few words with synonyms can leave you following the original sentence without understanding it. A stronger paraphrase rebuilds the explanation around the idea you understood. Read the source, look away and explain the point in your own structure before checking that its meaning survived.
Go deeper
Rebuild rather than disguise
Suppose a source explains a process in three technical sentences. Changing several words while preserving every clause may produce different wording without requiring much interpretation.
A genuine paraphrase starts from the meaning. Identify the main relationship, then explain it in a structure that makes sense to you. You might begin with an example when the source begins with a definition.
Afterward, compare your version with the source. Check whether you dropped a condition, strengthened a cautious claim or changed what caused what.
Using your own words does not remove the need to acknowledge borrowed ideas. The purpose of paraphrasing is to make understanding visible while preserving the substance, rather than merely making copied wording harder to recognise.