When first creating an album for a singer (in the realm of Taylor Swift, Nicki Minaj, or Rihanna), a record label will rent out about 10 different studios around the country and fill it with the best songwriters and producers that they have on tap.
Once the melody and lyrics of the song are decided upon, the tracks are mixed and mastered by the producers. Producers can make up to $20,000 per track and the songwriters usually make around $15,000.
Once a decent number of songs have been made, the artist is called in to pick their favorite ones. The record label will always guide this process because they have teams of people doing market analysis to determine the best selling songs of the bunch.
Once the songs are picked, the artist will go into the studio with vocal producer and record all of their vocal parts.
Vocal producers work with the artist to get the best sounding takes for each track. They can get paid $10,000-$15,000 for each track that they produce. After this, the song is finished and ready for marketing.
Labels will pay for the song or album to be advertised as a banner on iTunes...
...and put on billboards all over big cities.
They will also have the artist go play some free radio shows...
...and give interviews afterwards. Sometimes it takes a free radio show and interview, plus a fancy dinner for the radio execs to get the song put on the station, but usually this tactic is used for further exposure.
All of this combined makes the song or album so visible that it is almost impossible for the general public to not be exposed to it.