If you can't do plumbing I'm not sure a sump is the filter method for you.
Is your tank drilled?
If not you'll need to build an overflow system as well as run the plumbing for the sump.
Sumps are usually under the tank as they aren't very pretty and it's easier to get the water to flow correctly in that configuration.
I would look on youtube, there's tons of videos on DIY projects there, including many on overflows, wet/dry setups, sumps etc.
Is your tank drilled?
If not you'll need to build an overflow system as well as run the plumbing for the sump.
Sumps are usually under the tank as they aren't very pretty and it's easier to get the water to flow correctly in that configuration.
I would look on youtube, there's tons of videos on DIY projects there, including many on overflows, wet/dry setups, sumps etc.