so, oracle xe / express 11g
and we want to use linux because its free

01. which linux?
Your best bet easiest life is Oracle linux
I did try with ubuntu but finally give up due this and that not exists
if you still insist on another linux other than oracle linux, then this guide is not for you

02. what to keep in mind when install oracle linux…
im windows users, therefore desktop will safe my life little bit
so, when installing, customize now, add desktop components
groups from the “Desktops” section:
◦Desktop Platform
◦General Purpose Desktop
◦Graphical Administration Tools
◦X Windows System

03. if you use virtual box, don’t forget to change the network adapter to bridge

04. install oracle linux, make sure the HOSTNAME is fixed and you dont want to change it again in future

05. install oracle linux

06. add firefox to your oracle linux
yum install firefox

07. update hosts file on linux –> /etc/hosts
put your host name at there
its something like HOSTNAME

08. install oracle xe
follow this guide
its totally same, i wont repeat
you should not have any error and configuration is done

09. Get start with database, see if your localhost:8080/apex working

10. try to connect other machine to your new oracle db, in case of network failure, check oracle linux firewall stuff
if you lazy like me, just kill it

11. play with your oracle xe on linux !