As a general rule of thumb, you may wish to consider running this strategy approximately 30-45 days from expiration to take advantage of accelerating time decay as expiration approaches. Of course, this depends on the underlying stock and market conditions such as implied volatility.
You may wish to consider selling the call with a premium that represents at least 2% of the current stock price (premium ÷ stock price). But ultimately, it’s up to you what premium will make running this strategy worth your while.
Beware of receiving too much time value. If the premium seems abnormally high, there’s usually a reason for it. Check for news in the marketplace that may affect the price of the stock. Remember, if something seems too good to be true, it usually is.