People who are visual tend to have larger messes than others. If they are emotional people they tend to collect too much and most of it is not contained. If they are more linear in their thinking they'll most likely just hoard papers. It's a common theme among collectors. Identifying your areas of weakness will help you visualize your next steps. If you're self-motivated you will accomplish more than if you are told you need to clean up. It may not be easy but it can be rewarding.
Start with easy things first. Start in the room you care the least about in your home. For instance a bathroom. That might be a good place to start since it's smaller and probably has less than other rooms in it. Bring garbage bags and some bleach wipes with you. Pull everything out of the drawers and place what you're keeping on the floor or counter. The old, expired and worn out items go in the trash bag. Using a bleach wipe clean out the drawers and the outside rails of the drawer. Put the items you're keeping back in the drawer. If it's a large drawer you might want to think about purchasing some drawer organizers to hold your makeup, brushes, etc. Measure the length, width and height of the drawer before purchasing anything. It's easier to build the module/organizer than buying one with several sections. That way you can design around your needs.
Do the same thing with the under sink cabinet. Pull everything out and only put back what you use. Using a clear plastic basket or a basket with no lid will help contain these items and catch spills. Only purchase items that you can use anywhere in the home so they can be re-purposed if not used in the original space it was purchased for.
Once you're through with the smaller areas it's easier to get to the larger rooms. Make sure that you don't get overwhelmed and quit. That would be counter productive and you'll get depressed about not finishing. It's better to set a tangible task such as one area, one spot, one counter than to look at a whole room and attack it. If you need help call us. We love organizing and decluttering!