How to best transfer iTunes Library from old iMac to MacBook and keep on external drive?

I want to transfer my iTunes Music Library, currently on my 10 year old iMac, OSX 10.9.5, to my MacBook. The Library is too large to put on the laptop's internal hard drive (185 GB), so I will need to keep it on an external drive. I am running iTunes 12.6.2.20 on my iMac and 12.9.5.5 on my laptop. What is the best way to make this transfer? I want to make sure I retain my playlists, along with the music.