One option is to place your bets when they are first released. Football bet lines are released a week in advanced. If you have a good reputable handicapping service that gives you accurate picks, then go for it. There is some risk in betting early like the line reversals might fluctuate depending on the public percentage. To fix that, you can place a second bet to lower your risk level.
Another option is to place your bets 30 minutes or less before the game starts. If you have a service that uses effective data, you can get the most information, which can offer profitable results.
Last option is to place your bets in-game. Placing a bet right at the beginning of a game is a fairly new approach in sports betting. This gives you the opportunity to get a feel for how the game might progress and how the teams are performing. Check the confidence level of your handicapping service to see if they match up with how the game is progressing and place a in-game bet.
When using any of these options be aware of the public percentage and line reversals if there are any.
Hope this helps you out. Best of luck!