So, for example, when your grandmother who has already passed away shows up in your dream, the dream is not likely about her, but her presence is symbolic. Or, when an ex-boyfriend keeps popping up in your dream, it's probably not about your old flame, but he is symbolic for something else.
It's About You
A central tenet I cover in the book is that most dreams are talking about you, regardless of who shows up in the dream. Dreams often deal with the heart issues that are current in our life (i.e., the anger we're wrestling with this week that showed up when we almost kicked the cat).
How to Interpret Your Dream's Symbols
First, write down your dream. You'll be surprised at how much easier it is to remove emotion, assumptions, etc. from your interpretation when details are on paper.
Second, assume most of the central items in the dream (place, people, colors, etc.) are symbolic clues pointing toward a common message.
Now, what do those symbols mean?
Symbol dictionaries can be quite helpful as a starting point to decode a symbol's meaning, and a good Christian dream symbol dictionary should start with the Principle of First Mention (more below). Go through the dream and write each symbol's meaning next to the symbol (there is a biblical-based symbol dictionary in the last chapter of Dream Interpretation Toolkit).
Principle of First Mention
If you don't have a Christian symbol dictionary, or your symbol isn't in the one you have, you can use the Principle of First Mention. Simply: the first time a subject is mentioned in Scripture, it establishes a fundamental pattern of its symbolic meaning.
For example, the color red is first mentioned in Genesis 2:19 as the name Adam, which is Hebrew for red or ruddy. Adam also means blood-colored. Considering these first uses of red in Scripture, we find the root meaning of red is blood. As Christians, this of course speaks of salvation, Christ's work. Red clothing often symbolizes Jesus, because His blood was shed on the Cross, and Revelation says His garments were stained red.
Symbols can have branch meanings as well. Dark red is the color blood, but of dried blood. Dark red often symbolizes our hearts that once were wholly for the Lord but now His blood is "old" or "dried up" to us.
Symbols are a type of figurative language used in the plethora of ways God speaks. Symbolism speaks to our heart more than to our logical mind. It basically bypasses our noggins.
This might be hard for some to swallow, but surprisingly often, the God of the universe also uses symbols for their slang meaning. For example, we say a person is "hot-blooded" when they have anger issues. A person in your dream in red clothing, or driving a red car, or with red hair could therefore symbolize anger.
People, Colors, and Places are Big Keys
People, particularly the ones you know in real life, are important keys and are the first symbols to figure out to unlock your dream's meaning. Ask yourself, "How would I describe this person in real life?" Are they sweet and funny, but also temperamental and moody? Are they struggling with an addiction? Are they superb at attention to detail, but somehow also make you feel less-than with all their nit-picking?
Now, look at your life: What of those things have you been doing lately? Are you sweet and funny, but have been moody and it's affecting those you love? Are you secretly struggling from an addiction? Has your perfectionism, which usually is such a gift, crossed a line into making others feel constantly judged?
The thing you currently have in common with the person in your dream is likely what they symbolize.
Look for Threads
Now, with all those symbols' meanings written out, what are the repetitive threads you see? Are there three or four symbols that could mean anger? Have you been angry lately? God's probably talking to you about that.
Are there several symbols you could interpret as fearful? Are you struggling with some kind of fear now in your life?
Ask God for Help
God talks to us through dreams, and often He's dealing with our hearts. Not because He's angry at us, but because He's constantly working, in anyway we will listen, to make us more like Jesus.
Once you see the dream's threads, ask God to show you your heart in that matter. You'll know if He's putting His finger on it. Often He's leading us to repent, make things right, and get our hearts clean, so we can be closer to Him.
I find that when dreamers shift to assuming the people and places in their dreams are symbolic, not literal or prophetic, that they start to experience the "a-ha" moment of understanding. Try interpreting your dreams as symbolic first. Write out your dream, underline the key people, places, colors, numbers, etc., and then determine what those could symbolize. Your dreams will likely take on a whole new meaning.