I have a Little Giant Still Air incubator, without the auto turner, and have had really good results. I actually have the incubator in my home office because the temp. is always about the same there.
The first thing you want to do is let your incubator run at least a day, make any corrections to the thermostat control, it can take several hours to stabilize the temp. I found that the thermometers that come with the incubator are not that accurate. I went to
PetSmart and bought a digital reptile thermometer, it has a long cable/wire with a sensor on the end, I just stick the wire/sensor through one of the vent holes so that it stays right about the top of the egg level (you will want to remove one of the red vent plugs). You will then want to fill all of the water trays, there are 3 total, with warm water. Depending on humidity outside, you can add water weekly or so, just keep a check on it. Also, you want to keep the temp at 102, not 99.5, if your incubator doesn't have a fan.
Once your sure your temp is staying at a constant 102, you can put in your eggs. Let me know if you have any further questions and I'll be happy to help!