This will depend on your particular situation. Some advertisers want to maximize the number of impressions and clicks they can get at a price below their max bid and those set a large budget, not expecting to spend it on most days. The role of that budget is just to protect them from large unexpected variations in demand.
Other vendors are sometimes tightly constrained in how much money they can spend per week or month on advertising. If you are in that situation, we recommend setting the budget in a way that if you spend the whole daily budget every remaining day in your planning horizon, you will not overspend. The reports in the dashboard will make it easy for you to monitor your spending and how much customer attention it delivers to you.