By Public Transportation
If you are using Transmilenio, you can get here from anywhere in the city. You must take a bus that says AGUAS or UNIVERSIDADES. You will identify them because the bus number also has a letter, in this case, J for example J24, J23, J72, these routes will stop at the stations Aguas or Universidades. Once you go to any of those two stations, you will be very close to Monserrate hill, you can get there walking (10-15 minutes), take a taxi, a taxi should charge you approximately between $5000 to $6000 Colombian pesos.
In the following link, you can check out the different routes available in the city.