When you go to put the new seam sealer back cut the tip at a 45 and dont cut the tip hole so big,This will make it easy to lay a thin line.Keep a wet rag close by and clean your finger on every run.If you use a caulk gun.
I think my main problem was I didn't grind down the tack welds any. So some were bigger than others and that messed up the smooth look I was looking for.