I've read a number of blog posts recently that extol the virtues of using a countdown timer while writing. Indeed, setting a limited, immediate writing goal is a terrific way to help yourself focus. You effectively carve a slice of time out of your busy day and set everything else aside, knowing it'll still be there for you later. It's important to remove distractions so nothing interferes with your concentration! A timer can sure help you churn out the work.
To keep yourself fresh, write for 50 minutes, then take a 10 minute break, then write for another 50 minutes, etc. Breaks help. We need to clear our thoughts, release the tension, get some oxygen (get up and walk around!). Breaks help us return refreshed and ready to focus for another go-round.
If you don't have 50 minutes, you can set a shorter writing goal (10-15 minutes) and fit several smaller writing sessions into your busy day. This is a great way to keep in touch with your story rather than dropping it altogether when time is limited. By keeping the story moving, even slowly, you keep it from growing cold; when that happens, you need extra time just to get back into the flow of things before you can write productively again, which means you lose time.
To keep your work on-track, set a specific writing goal for each writing session. For example, "I'll use these 50 minutes to write a first draft of this scene or chapter," or, "I'll use this writing session to edit the last chapter and plan the next chapter," etc. A timer creates immediacy, but you need to complement that with a specific writing goal in order to achieve true focus.
I found a free timer called "Cool Timer" which you can download here. CNET is a great site for technology reviews, downloads, etc. The download is certified spyware-free, plus you can scan it with your own anti-virus software once you download it (just right-click the downloaded file -- you should see an option on the pop-up menu to scan it with your anti-virus software).
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