I have a collection of Good Seasons salad dressing bottles I've learned to use and make my own seasoning for the dressing from scratch. (much cheaper) These bottles can be found at Goodwill stores or in yard sales for cheap too. (on ebay or etsy they can go for $25 as "vintage")
But you can use any jar. I have several like the one to the left.
If you purchased an envelope of Good Seasons (or a knock off at Walmart) you would add it to the bottle. The bottles have lines on them for adding oil (1/2 Cup), vinegar (1/4 Cup), and water (3 TBsp). Then the seasoning is added and the bottle capped and shaken vigorously and allowed to rest for a half hour to an hour before using. The choices of oil & vinegar are up to you.
If you want to make your own Good Seasons mix for Italian salad dressing here is a recipe:
2 TB Oregano, 2 TB Salt, 1 TB Onion powder, 1 TB Garlic powder, 1 TB sugar, 1 TB parsley, 1 tsp ground Black Pepper, 1 tsp Basil, 1/4 tsp Thyme, 1/4 Celery seed.
This can also be mixed with flour to coat meat before frying or if you want to make a meat marinade, use 2 TB of the mix, 2 TB vinegar, 1 TB water, and 1/3 Cup of oil.
Celery Seed Dressing
1/2 Cup sugar
1 tsp mustard powder
1 tsp salt
1/4 of a grated onion
1/3 Cup vinegar
1 Cup Olive Oil
1 TB Celery seed
Mix the sugar, salt, mustard, and onion together, then add the vinegar & oil to the mixture to combine. Last add the Celery seed and mix well again.
I had a great aunt who used to use this all the time. Like many women (and she was a widow) she was always worried about her weight. So for the oil......she used mineral oil that she purchased at the pharmacy. (food grade mineral oil)