A solution to those would be cable management. But cable management is not always applicable/easy for most cases out there and buying a good case would cost you a chunk of money, generally ranging from $80 - $300.
Here I introduce to you a step by step tutorial for those people out there who owns a bad/small case.
Read and see how to transform poor cable management to good enough cable management.
Step 1: What Is a Bad Case?
Technically a bad case is a one with poor cable management features and poor thermal management. Therefore leading to dust buildup and high temperatures.
As you can see in the image poor cable management would mean less than an inch of space between the rear cover and the motherboard mount. Also few or no cable manage holes/gromits in the case.
Step 2: You Will Need..
-Phillips head screwdriver
-Long nose pliers (only used for tightening cable ties which would only depend on your strength)
Step 3: Opening Your Case and Removing All Plugged Connectors
Open the left and right side panel of your case. If you have a fan installed on panel/s you might want to open it slowly to avoid stressing the wire attached.
Remove all plugged connectors from your power supply also your SATA connectors. To do this you apply enough pressure to pull it but not enough to break them. Generally for 4-pin/4+4-pin, 20-pin/20+4-pin and 6-pin/8-pin PCIE connectors (see images). You need to press the lock above the connector to remove them.
Step 4: Routing Your 24-pin/motherboard Cable
Cable tie the cable and make sure to cut of the excess using cutters.
Step 5: Routing Your 6-pin/8-pin PCIE Cable
Step 6: Routing Your Molex, Sata, Sata Power Cables and Other Cables
When connecting fans, it is better to daisy chain them (connecting the one to the other) rather than plugging them one by one to a molex connector. That way you would only need one molex connector for your fans and saving the rest for other peripherals.
Step 7: Some Tips and Other Info
You can make use of molex to SATA power adaptor if you lack lack a SATA power connector or in my case I used it so that I could use my molex connector to power my hard drive and not used another cable from the power supply.
If your cable ties are too short you can connect one to another to extend them.
To hide unused cables like floppy cables you can twist it around itself so that it is neatly tucked in and does not prevent airflow.
Lastly if you don't understand something or you're having a hard time at following this guide you can always do your research there are lots of cable management guides out there each having their own ways to do it. And one more thing:
"Logic will get you from A to B. Imagination will take you everywhere." -Albert Einstein
Be creative. :3
Step 8: Credits
Posted on instructables on 08/21/2011.
Credits to http://www.playtool.com/pages/psuconnectors/connectors.html for the power supply connectors images.