I have taken most of my advice from the expert of all experts, Stephen LaBerge, and will share the methods I use…
Of course keep your DJ right next to your bed and always write down the date. I write down the date before bed each night (when I awaken it’s one less thing to write that’s not a dream) and even if I have zero recall, I write how much sleep I got, how I felt upon waking, etc., to help me during future sleep.
If all you can remember is a mood, feeling, person, one little thing, write it down.
If you wake up in the night, write down your dream, don’t wait until morning or you will probably have lost it.
I think the “events of the day” idea you refer to is if you don’t remember a dream or all of a dream, the day’s events may cause you to remember a dream. If you are like most people, you should have no trouble distinguishing real memories from dream memories. Personal example: putting a new roll of toilet paper on the holder one morning IRL caused me to have a brief memory of my boyfriend putting a new roll on the holder the day before and I said wait a minute, he never does that IRL, so it must’ve been a dream memory. I checked with him to be sure and I was right (plus there’s no way I go through a roll a day). Funny trigger for a memory and funny dream too, but any memory is a good memory!
You can give your dreams titles to help them stand out in your DJ for later reading and reviewing if you want (can help you pick out common dreamsigns and make it easier to locate a particular dream you may be looking for)…I rarely do this even though Dr. LaBerge suggests it. Personal preference, it’s up to you. I’ve only done this once and the title was “The Should’ve Been Lucid - Giant Praying Mantis - Pot Yard Sale Dream”. Don’t ask. 
Sometimes when you awaken if it was a vivid and lengthy dream you may want to jot down a few words about various parts of the dream so you don’t forget them and then you can write the dream out as you remember it in detail, using your notes to refer back to so you don’t leave any parts out. I don’t usually do the note thing but I’m going to start because it helped me the other morning. I had written down about a half-dozen highlights from a dream and by the time I thought I was done writing out the story, I checked the notes again and realized I had forgotten a whole scene that fast, but having the notes brought it back into my mind and I was able to write it down in detail.
You should describe as much of the dream as you can, especially anything very odd (something that could be a lucidity trigger in the future). Describe the actions, the sights, sounds, smells, emotions, everything! You can also draw pictures to add to your dream story; I’ve done this many times.
You should also leave yourself enough time in the morning (or whenever you get out of bed) to record your dreams (wake up earlier than usual). If you’re in a hurry to get someplace, you won’t have time and that sucks. If I have a really long dream, it can take me 20 minutes or so to write it down.
Just remember this, it’s your dream journal and you can set it up however you want (however you experienced the dream is the best way to write it down as far as the story part), but these tips should help get you started and I’m sure there are other dreamers here who can help you.
I thought there was a BIG dream journal topic, but I guess not? I mean besides people’s individual dream journals, I thought there was a topic on setting them up and stuff…?
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