Daily Forecasting Model Suggestions

[PacNW]

Hi there,

I am looking for general help and may be posting in the wrong forum. Please let me know if I should post elsewhere on the site.

I am building a daily forecast model of retail sales:

The daily sales are impacted by:

Day of the Week
Day of the Month (the sales are to customers that become more budget constrained towards the end of the month)
Holidays
Shopping seasons
Macroeconomic conditions
(a bunch of other variables - industry specific)

What I have been using is a lagged dependent variable model with dummies for weekdays, dummies for holidays, a shape for the shape within a month, and variables for macro conditions.

What I am struggling with is how to incorporate the modeling of seasons into this type of model. They are much like seasonal waves rather than explicit start and end dates.

I'm also open to recommendations for typical econometric models that are commonly used for this type of modeling. I am guessing that this is a common enough type of forecasting need (daily sales) that there is a somewhat common model used.

Does anyone have any ideas/feedback?

Also, if you know of a more appropriate forum (outside of EViews), let me know. I work in such a niche industry that sometimes its tough to do this work solo without resorting to hiring a consultant.

Thanks!!