STL files, used for 3DPrinting can come in a few different flavors and formats, but the following are some basic tips for exporting STL files from professional CAD software.
First of all, make sure your design is printable and manifold. The important things are being manifold, being of the right units, and being the right version of STL.
Your STL must be manifold, or in other words, water-tight. Most CAD software takes care of this automatically, but some programs like Trimble SketchUp can export non-manifold STL files, which must be repaired before they can be printed. You can repair STL files in many ways, including NetFabb Cloud. KISSlicer, and most STL viewers will give warnings if the STL file needs to be repaired.
Units should always be set to millimeters. In 3DPrinting, the machines and software all use millimeters as the preferred unit of measurement. If you do not properly export to the right unit, the file will come out undersized (or if your unit was for some reason smaller than millimeters, oversized.) In fact, KISSlicer even has the ability to effectively scale from inches to millimeters because it is such a common mistake.
Lastly is the version of the STL file. Basically two versions exist; ASCII and Binary. It is recommended that you export to binary, because it is more compressed than ASCII, and thus takes less space. ASCII STLs can take up hundreds of megabytes.
Some STLs can be exported too high in resolution. The resulting gcode can be very large, and as a result even small movements of the machine might be made up of many tiny lines of gcode. When this happens, the amount of information that is being sent to the machine might be greater than the USB cable can handle or more than the Atmel Chip on the Arduino inside the machine can stomach at once. Sometimes, your machine might even become unresponsive.
The machine deals with this sometimes by stuttering - sometimes even for several seconds - before continuing. The solution is to export your STL to a slightly lower resolution. Anecdotally, circles will still come out great if they're really just 360 sided polygons. Most STLs aren't more than a few dozen megabytes.