For lawncare you should try this: Lawn signs, truck lettering, and last but not least door hangers.
Be aggressive, and use the rule of 3. For every lawn you cut, go talk to the neighbor to the left, right, and across the street. If they are not home, leave a door hanger. Your door hanger should say something like: We will cut your lawn for $xx this includes edging, and blowing off sidewalks/driveways.
When I first broke into handyman, i took on lawncare. I had about 2 dozen lawns just by talking to the neighbors. If I saw them outside, I yell over and ask if they wanted me to do their lawn next. It's a great icebreaker. Stop and talk to the neighbors. It was not unusual for me to get one house on a street through advertising, then take over the block once I got there.
Be professional looking, and use professional equipment. Lawncare equipment cost are outrageous. It's hard to start with a full on truck w/ a trailer loaded with a $5k zero turn and weedeaters. But strive to work your way up to that. Show up with a clean push mower, weedeater, and leaf blower. Heck around here I can go to rent a center and get a riding mower for cheap if need be. Look into that so you have a rider for the bigger lawns.
A clean nice truck is a must. It doesn't have to be new, but don't show up in a beater. Any of this make sense?