You need to provide a hostname for the server host.
Typically you can do this one of three ways:
1 Through a DNS Zone
If you have control of the DNS server for your LAN (assuming you only want external access; or control of a domain/zone DNS server for wider Internet access) you can add a host (A) record pointing a given name to the IP address.
2 Through Locally-Defined Hosts
On any machine you wish to access you can add a line to the HOSTS file (this is usually /etc/hosts under Linux, somewhere else under Windows and other OS) which itself has a mapping from a name to the IP.
The downside of the second method is you need to do it on every machine you want to access from and also, should the IP change, you need to change it in every hosts file.
3 Use a Dynamic DNS / No IP Service
There are a number of services (free and paid) that allow you to create and manage DNS records. You can use an account on these to set a hostname to resolve to the IP address of your server.
Anywhere online you would then connect to myhostname.myservice and it would resolve to the IP, which could be an external IP or a local IP as you choose.