I ve started writing songs with my band, but me an d my friend are havin trouble making riffs tht sound good with the lyrics.plzzz help.thnx.
Concerts I've Been To:
Aerosmith x2
A Life Once Lost
Motley Crue
Pearl Jam
My Morning Jacket
Velvet Revolver x3
Alice In Chains
Stone Temple Pilots
Iron Maiden
Red hot Chili Peppers
Lamb of God
Killswitch Engage
start with chord sequences.
It doesn't hurt to "borrow" ideas from your inspirations. So long as you're not kidding yourself that it's an entirely original idea.
just remember that technical is not always better sometimes the simpler things end up being your best songs
There are many answers to this question.

Here's a relatively straightforward one.

Take a few powerchords that you are comfortable with. Then would out the syllables of the lyrics you are intending to use. Try rhythmically synching the 2 together and see if that appeals. Don't expect classic riffs of our time, but it's a start for you in the process.
Are there existing melodies for the lyrics or are they currently just words on paper?

If you have free reign it's gonna be easier - read the lyrics and look for rhythms that jump out at you. Think bout what the lyrics are saying and what kind of mood they create. Is it fast or slow happy or sad?

Or throw the lyrics out and just jam til you get something that is really good. Then make the lyrics fit.

If there is a melody already with the lyrics then you should work the scale it uses and specific notes that may imply certain chord progressions. Work your riff from there.