As for keeping a wet edge: that's critical when using oil-based paints. Not an issue with quality latex paints.
Another hint: mix all the gallons together before starting. There will be shade differences between gallons of the same color and mixing together eliminates this.
Also, as others suggested and as th Hometime page recommends, you should not "cut" the entire room at one time, but instead just do manageable protions first so that the paint does not dry before you roll over it.
- 10 Old House Features We Were Wrong to Abandon
- 11 Tiny Bathrooms We Love
- 12 Insanely Easy 60-Minute Home Improvements
- Kitchen Envy: 10 Rooms We Love
- 25 Clever Ideas for Repurposed Storage
- 10 Surprising Ways to Cure Household Odors
- 11 Ways to Winterize Your Home on a Budget
- 10 Ways to Live Large in a Small Space
- 10 Eye-Catching Options for Your Front Door
- Dressing Up the Dresser: 11 Clever DIY Transformations
- 12 Hobbit Houses to Make You Consider Moving Underground
- 10 Ways to Use Mirrors to Your Design Advantage
- 10 New Uses for Old Doors
- How To: Paint EVERYTHING
- Man, Oh Man! 7 Unbelievable Guy Spaces
- Assembly Required: 15 DIY Kit Homes
- 12 Wow-Worthy Woods for Kitchen Countertops
- 10 "Neat" Garage Storage Solutions
- 10 Houseplants to Improve Indoor Air Quality
- How To: Clean EVERYTHING