Seeing as different markets are opening and closing throughout the day, there will be different kill zone times for different markets. The main two you should be looking at is the London and NewYork Sessions. The London session is based on the London market and anything happening in the European market. Many new traders enter the FX Market seeking fast, and active price activity.
Many new traders enter the FX Market seeking fast and active markets. With the open of the London session at 3:00 am(EST) and the Frankfurt market opening at 2:00 am(EST) liquidity starts to pick up by 1:00 am(EST) most days. London is the heart of the FX market with approximately 35% of daily volume transacted during this session.
As the US session begins at 8:00 am and the environment can change quite a bit as even more liquidity is entering the market; and this time it is coming from both sides of the table with both major markets open. Even though the London sessions closes up by 11:00 am the kill zone time for London session is between 2:00 am & 6:00 am. In that small window, you will have the most liquidity from the London session and the best chance to enter your positions for the early morning. Later in the morning, you will have another try during the NewYork session.
Much like the London session, the NewYork session is very volatile and offers multiple different opportunities to take positions. During the NewYork you will see different times liquidity rises, the first one being at 8:00 am when the market opens. The next big jump in liquidity will come around 9:30 am at the equities market open, following that you will see one last spike in liquidity come around 11:00 am (the NewYork reversal) before markets start to settle down for the afternoon. Often there will be major news events in the economy which will have an impact on the session no matter if it is the London or NewYork session. A big thing you should always be doing is checking for news events during the session before trading as those can also provide high levels of liquidity. The kill zones for this session would be between 8:00 am & 11:30 am
Key things to look for when trading the kill zones would be as follows for each chart time frame:
Monthly - critical support and resistance levels, Fibonacci, price patterns
Weekly - critical support and resistance levels, market structure and which part of cycle the chart is on, which level the chart is on, Fibonacci, monthly support, and resistance will be relevant, key pivot points
Daily - critical support and resistance levels, Fibonacci, pivot points from the monthly chart
4h - critical support and resistance levels, Fibonacci, price patterns, short term key support and resistance levels, pivot points from the monthly chart
1h - critical support and resistance levels, Fibonacci, pivot points from the weekly chart
M15 - high time frame support and resistance levels, Fibonacci, prior three days high/low, pivot points from the daily chart
M5 - critical support and resistance levels, previous three days high/low, pivot points from the daily, 3day h/l, daily PP, watching for the major kill zones at highs and lows of the day to get a good entry
You will want to look for entries on the lower timeframes, and you'll also want to determine your risk to reward. Your R:R should be figured out in your goal setting and trading plan, but you'll also want to watch for price to trade near critical S&R levels and try to trade in the direction of the market on a daily chart.