1. Read aloud from a hard copy of your manuscript. Whenever you spot a passive verb or a state-of-being verb, circle it in red. That will help you trap those weak verbs and passive statements. Then rewrite the sentence.
2. You can set most computers to flag passive verbs. In Word, under Tools, go to Options and click Spelling and Grammar and go to Writing Style. If you click that, Word will flag the passive voice. (Notice that I didn’t write, "The passive voice will be flagged by Word").
3. Do a global search for particular words. For example, passive words need a helping verb such as was or had. Don't feel you must delete every use. Ask yourself, "Does this work? Is this what I want to say?" (I used is in that sentence.)
State-of-being verbs are useful. That's why they're part of the language.