as above, for three phase and high amp gas migs generally heat range 2 is good for panel steel, and 3/4 for 3ml . with the wire speed set about the same, Generally wire speed is relative to heat range and most manufacturers of welders will show this with numbers 1 through 6 on both dials.
To much splatter (bird shit)and jerking is either the heat too low or dirty steel rust/etc.
If you manage to melt the wire into the mig tip your heat range is to high for the wire speed.
like all welds you want the wire to flow like liquid but move it fast enough that it doesn't blow through.
You should get something like this
with really light steel you start to incorperate dwell time, this is the time that the electrode is alive for, if you find you can't seam a panel sheet without blowing through it to series of spot welds one after the other so they join. it will give you the same effect as the above picture and also look tidy.
this is also good for long joins as it will not generate too much heat as to buckle and expand/contract the metal as much as seam welding.
here is a guide for you
