Suction isn't everything! I highly recommend buying a vacuum that you can adjust the suction for each floor type. Area rugs and low pile rugs should be vacuumed on a lower setting. They can have rubber backing that does not allow proper airflow for a higher suction, causing motors to overheat quicker.

TIP #1

Vacuum the room in multiple directions. Vacuum the whole room in passes such as North to South. Then do the Whole Room East to West. This ensures that you lift the carpet fibers and get the dirt worked out.

TIP#2

Slow Down! Vacuuming shouldn't be rushed. Slowing down to vacuum allows the brushroller to agitate the carpet fibers and work the dirt out. Rushing over top just gets the surface dirt.

Tip#3

Vacuum last. Cleaning should start ceiling down, so you don't put dust and dirt right onto your freshly vacuumed floors.

Tip#4

Pick up anything larger than a Nickel. Clean chunks of paper, socks, tissues, and any other large debris that may clog your vacuum.

Tip#5

Always check your vacuum over thoroughly before you start. Check the filters, how full is the chamber or bag? Is the brushroller free of debris and hair

This is a well written guide to floors

https://www.wikihow.com/Clean-a-Floor#Vacuuming-Floors

LASTLY

We have seen a lot of burned out brushrollers and powerheads due to "Shag" style carpets. These carpets have between 1" up to 2" fibers and really shouldn't be vacuumed with a powerhead. Setting a Vacuum on Hi Pile, or adjusting the height to high, isn't cleaning into the fibers. The suction is lost. The recommended method is to flip the rug over and vacuum the back, then vacuum the floor.

I really like this Video on how to properly clean these carpets.

https://www.youtube.com/watch?v=ix3kAK61czk