- Obtain the module from the project page at Drupal.org
- Copy imce directory to your modules directory
- Enable the module at: /admin/build/modules
- Create configuration profiles and assign them to user roles at /admin/settings/imce
- Test it at /imce.
- See imce-content.tpl.php for some configuration options such as absolute URLs ad inline previewing.
Notes:
- When you configure IMCE for inline image/file insertion into textareas there should appear an IMCE link under each textarea you specified.
- If you are uploading files containing unicode characters, it is strongly recommended to use the transliteration module that sanitizes filenames by converting characters from unicode to us-ascii. http://drupal.org/project/transliteration
- If you are using CCK, you may want to check the File field sources module at http://drupal.org/project/filefield_sources

Here are the applications that already integrated IMCE.

WYSIWYG:
Install IMCE WYSIWYG Bridge module and enable IMCE as a plug-in in WYSIWYG settings

BUEditor:
IMCE is integrated in image and link dialogs.

CKeditor(without WYSIWYG):
CKeditor profile->File browser settings->IMCE integration

You can visit the demo page for working examples.