By now you're probably either planning your strategy for Saturday's WBOS EarthFest or figuring out how to avoid Storrow Drive like the plague over the course of the weekend. With predictions of weather in the low 80s and partly cloudy skies, it appears that the folks over at BOS have picked themselves a beaut of a day to devote to free music and environmental friendliness at the Hatch Shell.

For EarthFest attendees, it might seem awfully easy to anticipate heading down to the festivities, but know that this isn't your ordinary, garden-variety free show. With three stages of music and booths planned for the Hatch Shell area - and that rather inconsequential 100,000 attendance figure - EarthFest is something that requires at the very least some coordination. In order to make the most of the kickoff to Memorial Day Weekend festivities, you've got to do your homework.

Consider Bostonist the kid who sits behind you in class and offers you a crib sheet - because we're here to break down the music for you, letting you know who is playing where and what to expect from each of the artists - although we encourage those who plan to hit up the Family Stage to check out the lineup for themselves. Bostonist tries to know music, but without Little Bostonists running around, we don't know our SteveSongs from Girl Authority and would hate to steer you wrong.

Boston Music Stage: 11 a.m. - 4:45 p.m.
- Mieka Pauley (11 a.m.-11:35 a.m.): We are more than a little envious of Mieka Pauley. The WBOS darling has a warm, silky voice that she can adapt to poignant ballad ("The Way It Is") or rock-out anthem ("Stronger"). She possesses a quiet intensity that makes listeners lean in when she takes the microphone, and she has a song in her canon about beating unruly audience members over the head with a guitar (badass!). But that's not all: the heralded songwriter also has a Harvard degree to her name: she graduated early with a degree in Biological Anthropology. We're suddenly suffering from an inferiority complex. Mieka Pauley myspace

- Tim Blane (12:45 p.m.-1:20 p.m.): Hooky, in a good way, Blane is known for putting out the songs that needle their ways into a listener's head. The songster brings more of a jazzy pop vibe than many of his fellow Boston singer/songwriter counterparts, but he's also capable of bringing a poetic hand to the ever-necessary ballads (the piano-driven "Undone" is a standout). Tim Blane myspace

- Chad Perrone (1:50 p.m.-2:25 p.m.): Bostonist has been listening to local guy Perrone for a long time now, and we've watched him grow from a sensitive singer-songwriter type to a sensitive singer-songwriter type with a whole lot of moxie. The former Averi frontman released his solo debut, "Used To Dream," a year ago this month, and we're big fans of the resulting work ("Let You Sleep" and "Somewhere Beside Me" are notables). Chad Perrone myspace

- Jake Brennan (3 p.m.-3:30 p.m.): So Jake Brennan's Pop-Ed contributions to Boston.com didn't last long, but the guy made an impression on those who weren't already familiar with his indie take on what he dubs "hardcore folk." Whether the masses liked Pop-Ed or not remains up to debate, but we expect that folks will swing by to see the familiar name live. Bostonist's take? Haters, give his Globe-free stuff a try. Jake Brennan myspace

- Will Dailey: With his rootsy rock and warm summer twang, Dailey sure doesn't sound like he's a New England boy. His latest, "Backflipping Forward" features the standout "Hollywood Hills," a song that manages to sound beachy and ragtime at the same time. Our bet is on Dailey to get the most folks in the crowd by the BMStage dancing on Saturday. Will Dailey myspace

Main Stage: 11:30 a.m.-6 p.m.
- Vega4 (11:30 a.m.-noon): The BOS crew has been boasting over their Vega4 coup for some time now - they started playing current single "Life is Beautiful" well before most of their U.S. counterparts, and now everyone's starting to freak over the dreamy pop and BOS has the band for EarthFest. Seems to be a win-win: BOS gets an up-and-coming name and the London-formed four-piece (two Irishmen, one Canadian and one New Zealander) plays a show that ties into one of its big interests: raising awareness about global climate change issues. Vega4 website

- Grace Potter and the Nocturnals (12:15 p.m. - 12:45 p.m.): Grace Potter and the Nocturnals are poised to become the biggest thing to come out of Vermont since Ben & Jerry's and those Phish pholks. The blues-driven dirty rock that generated buzz on self-released "Nothing But the Water" might be giving away to a poppier sound on upcoming release "This Is Somewhere," but the band sizzles on a live stage when Potter and Scott Tournet (the best guitarist you've never heard of) lead the way through the grooves. Make sure to take in the spirit-summoning tune "Nothing But the Water" - when the band performed at Copley last summer, the song seemed to prompt freaky breezes AND get the crowd onto its feet. Grace Potter and the Nocturnals website

- John Butler Trio (1:10-1:50 p.m.): We'll be honest, we don't know much about John Butler and his trio beyond "Better Than," the rootsy pop tune getting plenty of play on BOS these days. We've heard the band puts on a laidback sunshine kind of show, which is probably a good approach for a band scheduled to be consistently on the road through October. We'll be as interested as the rest of you in seeing how the Australian musicians take to the Boston stage. John Butler Trio website

- Mat Kearney (2:15-3 p.m.): Mat Kearney earned points during an opening stint for John Mayer at UMASS-Amherst in February. The singer-songwriter remarked that one of his songs was featured in "Grey's Anatomy" - Kearney wryly remarked that McDreamy totally made out to his music. He managed to make us rethink our thoughts on the Nashville artist - The delivery of that line, coupled with a strong set, made us more open to the performer's brand of spoken word/singing musicality. It works better live than on the album "Nothing Left to Lose," in which a listener is stuck thinking about how we wish he'd decide whether to sing or not. Mat Kearney website

- KT Tunstall (3:30 p.m.-4:15 p.m.): It's been less than a year since KT Tunstall performed on The Today Show and morphed from buzz artist to star. Numerous singles later, we're just as anamored with the Scottish lass, who brings a plucky likability to her live performance. We also love seeing a woman take to the looping pedal systems that have become commonplace in male singer-songwriter circles - for some reason, it's more rare to see a lady layering the sound. KT Tunstall website

- Guster (4:45 p.m.-6 p.m.): Guster is the hometown band among the main lineup for this year's EarthFest and they love (love, love) eco-friendly music, so it's fitting that the four-piece is serving as headliners of headliners. The band has been a trailblazer in the green movement now sweeping the music industry - Adam Gardner and his wife, Lauren Sullivan, founded Reverb in 2004, and the organization raises environmental awareness through music and musicians. And, um, Guster rocks. Guster website

All photos by Victoria Welch