Step 1. Go to: http://www.alanwood.net/unicode/miscellaneous_symbols.html
Step 2. Highlight the symbol you want.
Step 3. Go to Edit in the top menu bar of your browser (or word processor or whatever) and choose Copy.
Step 4. Put the cursor where you want to type the symbol.
Step 5. Go to Edit > Paste in the menu bar.
This will not work if you see question marks or some other weird symbol instead of what the list says. For example, I see a vertical bar or a box with an X in it instead of hearts in my Macintosh Firefox browser. Otherwise, it's a surefire way to snag those symbols.
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P.S. If you want to type alt + 3 or whatever number you need for a particular symbol, be sure that:
A. You are using the numeric keypad (shaped like a square and usually on the right side of your keyboard) and not the row of numbers along the top of the keyboard.
B. You have the "num lock" key set. Usually there's a little light that indicates that it's on.
C. You are holding down the Alt key first, then pressing 3.
Best of luck.