Using the CyanogenMod devices page, find a phone that's well supported by CyanogenMod. Buy it from your favourite phone store.
Put cyanogenmod on it using the instructions on the Cyanogenmod site. Better not to install "Google Apps" because they're proprietary.
Go to phone's Settings > Security and check "unknown sources". Using the phone's web browser, visit f-droid.org to download and install F-Droid.
Now install some cool apps from F-Droid and enjoy!
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It's what I do, too; I've never found a need for anything more automated than the steps Xylon outlines. Been using CM ever since my late, lamented OpenMoko phone became completely outclassed and was retired to a drawer.
Fellow of the FSFE (#1499)
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