All you have to do today is:
a) register the song with your author society.
b) if you used an arranger, then either pay him, or give him some points in the song registration form under arranger.
c) if your song lyrics get translated to other languages, either pay the foreign lyricist, or fill him/her in with some points in the song registration form.
d) if you want further persons participating in the earning via the authors society, then also fill them in on the song registration form.
e) Nobody makes old fashioned publishing contracts today. Except the record company demands that, but then you should ask what they do for you for their share. This shares where 50%/50% in the US, or 60%/40% (composer lyricist/publisher) in Europe.
Today the share between composer/lyricist and digital distributors are 70% for the composer/lyricist and 30% for the digital distributor.
f) if you are the producer and you payed the production fee, then you can demand up to 50% of the net.
g) if the record company payed the production fee, then the producer percentage from the net can be 5% to 10%. Some times up to 35% if the artist is a well known and an established artist/band.
h) If you are not an American and your music gets released in the USA, then exclude the territory of the USA in the song registration at your local author society. This because ASCAP and BMI pays more to their own member then to members of foreign author societies. All other authors societies worldwide pay the same to all, no matter what authors society you are a member of.
Done all that and you are ready to licence your recording to a record company, or to a digital distributor.
That's all!