One of the first things you will do when you begin customising your EPrints repository is to rebrand it with your organisation's branding and colour scheme.
In order to make a good first impression on your users you want a repository that looks good. Here you can find some tutorials to help get you up to speed quickly on the ins and outs of repository branding.
You can also get plenty of help on EP-Tech. For free support and discussion about EPrints you can sign up to EP-Tech.