I've been playing with constructed languages for almost 8 years now. That seems like a long time, but I didn't really get a good grasp of the concept until much more recently. I first got into constructed languages when I began learning German as a second language, and also started to write fantasy at the same time. The idea of making my own language sounded like fun, so I gave it a shot.
At first all I had was an alphabet cipher (like Daedric). Once I was confident enough with my knowledge of language, I began to invent my own words and grammar. I developed several languages for different fictional peoples, and even made a language for a friend's science-fiction story.
Eventually, one language, now called Almaril, stuck with me and has been reconstructed several times over the years. It's fairly developed, with comprehensive grammar, a written alphabet, and around ~800 words. I mostly use it to write poetry, and continue to use it in fantasy writing. A sample of it is below:
Myethavolgyr Myethavolgyr
Ci ara vir velthiran
Hu sulÅs nulmolir welkyreth
Qua sÅri vihedh aserev
Vet kai yiralt fum yev
Myethavolgyr, faha vir elmri u kiriyev.
Above is the "Song of the Dragonborn" in Almaril. If you have any constructed languages of your own to share, I'd be excited to hear about them!