When having flowers delivered, it's always nice to tip the delivery person $5. You're already happy because of the flowers, so spread the joy.
2.) Tattoo Artist
Tattoo artists are highly skilled individuals as precision is 100x more important given the permanent nature of tattoos. As a thanks, tip your tattoo artist 10-20% of the total cost of your tattoo.
3.) Dog Groomer
Dogs look so adorable when they come back from the groomer, and usually they're very happy to be clean. Say thanks by tipping your dog groomer 15% of the cost of the session.
Tipping plumbers or electricians isn't customary as they typically work on a contracted and agreed upon price. They also don't rely on commission. If, however, your plumber or electrician completes an extra difficult job and does it in an excellent manner, you can and should give them a couple extra bucks.
5.) Barber/Hair Dresser
Much like you don't want to mess with the people who serve your food at restaurants, you definitely want to tip your barber or hair dresser well if you plan on getting your hair cut (well) by them again. Between 10-20% of the cost of the haircut will suffice as a tip.
For a good bartender, you want to tip $1-$2 per drink, or 15-20% of the final bill. You never know, you could end up with a free drink or two along the way!
7.) Hotel Housekeeping
For those hardworking men and women that make sure your hotel is fresh and clean every time you return, you should tip at least $2-$3 per night.
While it depends on the amount and weight of the stuff they moved, but don't let your team of movers head out without giving them at least a $20 tip for their hard work. More if they didn't break anything.
9.) Taxi/Limo Driver
Being a taxi or limo driver is no easy job - it takes a lot of memory and driving skills. You should definitely tip your driver for getting you where you're going on time. The recommended tip is 15-20% of the total cab fare.