Yep hit it hard till the puddle forms(bumping they call it) get moving/dabbing and back off at the same time, depending on how big the piece your welding and how much "heat soak" it can take(the bead will look smooth if getting too hot)you keep backing off until your finished.
I 1st started on 1mmx20mm flat bar just couldnt get it to work melted the living hell out of it, was using 60amps(max) because I was hanging around for so long to form the puddle the whole piece was getting heat saturated... very frustrating without someone around to give ya a smack across the head and say no no no!
Turn it up too 120amps max slam the pedal down puddles in about 1~2 seconds get dabbing... then find your filler hand wont keep up after 50mm or so! So start with thicker section like 3mmx50mm(150amps)or even 6mmx50mm(180amps), you will soon find that the thinner stuff is very hard to do
Its the only way thats worked for me(very novice)so far, Im just starting to get the hang of ally after 5 sittings of a good hr each... starting is getting pretty easy finishing is tricky still

My machine is a Everlast 210ext with a W300 watercooler WP18 torch

Look up Welding tips and tricks on Youtube, Jody is about the best on there very easy to relate too.