copy and pasted from a different account but heres some info about the alters.

Garfield - Garfield is the parts of Orange that Orange either sees as "not him" or something he "shouldn't" enjoy. basically, Garfield is the alter where all of Oranges repressed desires have gone. He manifests as a very lazy, sluggish hedonist with very little concern for anything other than enjoying himself. he isn't malicious or violent, which is actually a very notable trait for him to lack since a lot of Oranges alters are defined by need for physical protection, and that's something Garfield lacks. Garfield enjoys long long long naps, weekends, Blues cooking, his watermelon sunrise drinks he makes in minecraft, and being pet and babied. Orange is often ashamed of these traits that Garfield holds, so when Garfield fronts, he tries to stay in front as long as possible as to not ruin his fun. He gets very frustrated when he gets interrupted by things- which is often the CG being in trouble. Due to this, Garfield is the least attached to the CG due to them often being the cause of him not being able to front consistently. Garfield also has a tendency to feel like he "deserves" to be pampered because of how much work he does for the CG, and gets sort of moody if they aren't willing to play with him how he wants. Garfield is the parts of Orange we see in the series where he doesn't give a fuuuuck about anything but his Treat like in killer bunny or the most recent teamwater short in the waterslide, or the short with him falling asleep when Blues trying to cook a chicken.

Second - Second is Oranges trauma holder, and we actually see him in canon! In the showdown after all his friends get killed and his powers start to manifest we see Second take over and is filled with a blind fury towards The Dark Lord. I imagine Second very similar to how I imagine the Chosen One behaving (since they're related) where Second denies himself of enjoyment and good feelings because he feels like he needs to constantly be on guard. Second has intense survivors guilt and a constant need to protect and keep his friends safe, as well as a feeling that he can't trust the CG not to get hurt if he leaves them unattended. Second also fronts very frequently along with the host, but hides from the host because he's the trauma holder and doesn't want the trauma to bleed over into his every day life. Second often feels like a monster and a dangerous tool, and doesn't like to front around his friends due to this. When he does front, he's extremely awkward, a by the books rule follower who feels like safety is the most important thing over everything else. He's a party pooper, and extremely violent. I imagine Second is who we see beat the fuck out of Red during the lush caves episode, or during the pop up short.

Cowboy - Cowboy is another alter we see in canon during AVE, and i consider him an alter that exists to help with communication. He wears his hat to differentiate himself from the others and to signal himself as a sort of Cool Guy. i imagine Orange has a lot of ideas of what "cool" is and what he wants to be, and Cowboy ended up absorbing a LOT of that. I imagine he quotes movies constantly, and regularly has that shit eating grin on his face because he thinks he is just So Awesome. he is one of the lower anxiety alters, and is good at finding fun within stressful situations. He is what Orange strives to be, and that helps a lot to get Orange to trust him when trying to build bridges for communication between Orange and Second, who don't communicate at all despite being cohosts. Cowboy is incredibly playful, but I think he can get caught up in his own actions sometimes, if he's enjoying something he might play into it a little TOO hard and not know when to stop because he thinks everyone else is enjoying it as much as he does. Cowboys violence comes not from aggression but a need to show off and an enjoyment of the physical activity. He can be a bit of a "trickster" in personality. I imagine Cowboy is the one we're seeing in shorts where all the characters show off their weapons or are play fighting just for Orange to come in and totally destroy them with whatever OP weapon he's drawn himself. Cowboy is also the one I imagine fronting during the LOL episode when he decides to be the bad guy at the end, or during his minecraft speedrun.

Host - Thats Orange! Or at least the version of Orange that fronts the most. He is anxious, friendly, and enjoys playful competition. Basically this is the "outside" version of Orange his friends see. He can be a bit controlling, and WAY too violent, but also doesn't tend to see either of those things as a problem. The control is because he worries for his friends, and the violence is because its either fun or necessary. Orange is unaware he has DID and doesn't know what's going on with his emotions which causes him to feel very very disconnected and spacey a lot, he sort of assumes if he does have emotions he doesn't feel them strongly. Orange is a bit hard to define because he's a mixture of all these guys! His defining trait among them is his anxiety, and his worry. Always worrying about everybody.

Sketch - Sketch is Oranges first alter that was developed immediately after watching the CG get deleted by Alan in AVA3. Originally Sketch was developed as a way to help cope- and more importantly, physically destroy the desktop along with Orange. Sketch is actually the only alter whos physically existed "outside" of Oranges body because he's drawn Sketch multiple times in different forms through out the series, but it's always the same part being projected outward. Sketch is now the part that works with Alan as a part of his job, and speaks most to Alan. Sketch exists as a "partner" or a second self for Orange to bounce off of, his imaginary friend who acts very similar to him. As time goes on, Sketch starts to represent "early series" Orange, who he was before the repeated trauma he goes through that makes him a lot more high strung and anxious, and I think he often resents that. Sketch can be multiple things though, and is moreso defined by his role as an imaginary friend and protector than any specific like or interest. Sketch does not front often unless Orange is alone- i imagine any time Orange has a scene where he is imagining himself "doing" multiple things without actually doing them, or is imagining the CG there with him when hes alone- those are all actually Sketch filling the role.