In addition to saving money, I like to save time. So, my advice of the day is to go to businesses during their offpeak times. Each business is different so just ask an employee. I asked employees today, and this is what I learned:
Walmart: 9am No Lines! They said most Tuesday aren't busy and definitely most weekeday mornings.
Simoniz Car Wash in Panther Creek: 9:30am was empty. They said Tuesday and Wednesday are the least busy and Friday, Saturday, and Sunday are the busiest
Panther Creek Post Office: 9:30am No wait. I went Saturday around noon and there were 25 people ahead of me in line. Try the automated postal center when there is a line.
Fuddruckers: 11am. A lot of restaurants open at 11am. Most aren't busy when they open. We were still the only ones there at 11:35am when we left.
Kid Gym Open Plays. Find out when they are empty. Some open plays have zero attendance.
HEB: Definitely busier on the weekends.
Chuy's isn't busy after 8pm on weekdays. Crazy on weekends.
etc... You get the idea. Feel free to email me or leave a comment with the off peak times you have found!