1Mix onions, bell peppers and squash in large pan, sprinkle with the salt. Let set one hour.
2Bring to boil vinegar, sugar, celery seed & mustard seed. (celery & mustard seeds may be put in a cheese cloth bag to be removed before adding squash, bell peppers & onions, I prefer the seeds in my pickles)
3Press water from squash, bell peppers & onions with hands, drop in boiling vinegar. Bring to a big boil, count 5 minutes.
Put in clean hot jars, with hot lids & rings. These will self seal.