i'm not bad at them but there is room for improvement. Can you guys give me any tips on how to make my slices and lobs more efficient and consistant?
Funny enough, these were the first two shots I learned when playing tennis. This might be because I started with my friends in the park when I was 11 or 12 and they sucked worse than I did! Only ever hit with slice, and lobbed the tar outta my friends who couldn't hit a smash to save their lives (not that I was any better, but they didn't exploit it!)
Anyway, for lobs my tip is topspin. Lots of it. You can loft the ball up really high and it will still come down inside the baseline given enough top! Also, I like to occasionally hit a lob in a baseline exchange to break things up. Many people dislike the change of pace and spin.
The same changeup motif holds true for slice. The tips of high to low swing and leaning into the ball are very good. Use slice on approaches, it makes it much tougher for your opponent. Personally, from the baseline only
I aim for the top of the tape when slicing, as the ball falls far less sharply than topspin or flat shots, and the open face of the racquet makes the ball go higher than where I aim it. Very rarely do I dump a slice into the net this way; usually it goes nice and deep. This may not work for you.
Practise and see!