I find it useful to use time filters for when to trade and when not to trade.  One way to maintain these filters is to keep a record of your trades, sorted by trade method.  Then for any particular method, every week or so take a look at the past 200 trades and break these down into 30-minute periods during the trading day. If three or more consecutive half hour periods show no profit, then you should consider NOT trading during that time of day.  This means a lot of busy work, because even when you are not trading during that time, you need to be paper trading and entering those trades into your spreadsheet so that you can continue to monitor and update the efficacy of your time filter. However, this simple method can increase your profitability by as much as 25% or more.  Is it worth the effort to mark your trades in a spreadsheet, in order to  save several thousand dollars a month?  That's up do you.

Once you have determined when your "Go trade zone" and "No trade zones" are, you can mark them on your chart automatically.  Ensign has a nifty feature that allows you to do this.  Howard's explanation and settings are shown here:

I use the Zone coloring tool to change the background color of my entire chart to dark red during my "No Trade Zone":