Writing a song with lyrics

so I want to make a song but I dont know where to start
quite often ill write some lyrics and create a main rhythm and tune of the song
but then ill find that they dont fit together
so wats the easiest way to create a song

starting with the lyrics then...

basing the tune around the lyrics?
or starting with the tune then basing the lyrics around the tune?...

and also, I've only got an acoustic guitar and unfortunately dont have enough money to buy a bc rich which I would loovee..anyways

so, how can I make my acoustic guitar sound more heavy..if its possible.
is there any thing I could add to my song to make it more heavy..
or give it that more of a metal sound?
lol I know it sounds silly because you obviously cant get a metal sound without an electric guitar but...anything?
or maybe something I could add to my lyrics..

hope someone can help..

Aw great question. I often wondered this myself.
I have come to the conclusion that you should write the tune first then wrap the lyrics around it, but if you heard any of the songs I wrote you may not want to listen to my advice lol.

I dissagree... the lyrics should express something so the lyrics should be the main thing to do. then wrap the tune around the lyrics... if you find a beat that you like keep it! and then base a song on that.

I write a lot of songs and I dont really think it matters which you make first lyrics or rythm. For me I usually make lyrics first but thats just me..good luch

check out the lyrics I posted and comment me please

As I stated I'm no John Lennon but isnt it easier to change words without changing the meaning of a sentence. What I mean is, once you have the music written and a beat set isn't it easier to change words so the syllables fit than change the music to fit the syllables?
Just my opinion though.

if you want a heavier sound on an acoustic try detuning to D standard or C standard, when I write I do it riffs first lyrics second, hope I was some help