Everyone can do this in their own way, but I prefer to do it in my own, structured way. You come here and post info on your characters. Here's my main example.

Name: Blood Striker
Occupation: King of Mobius, God of Balance/Mischief
Age: 2000+
Race: Hedgehog
Favorite weapon: reverse blade/scythe
Relatives: Biyoko (lover), Miles Prower (brother), Saya Striker (mother), Zaldin Silverwind (father), Valek Silverwind (half sister), Shadow Striker (son), Sonic Striker (nephew), Mirage Striker (elder sister)
Profile: King of Mobius. Cares deeply about friends. Prefers to not fight.
Likes: Family, being king.
Hates: Fighting, those who pick on/endanger others.
Gender: Male
Fur Color(s): Red (primary), Orange (secondary/chest fur)
Picture:

Name: Miles Prower
Occupation: genius, father, prince
Age: 23
Race: Fox
Favorite weapon: electrical cord, hidden in tails.
Relatives: Blood Striker (elder brother), Saya Striker (mother), Zaldin Silverwind (believed father), Mirage Striker (elder sister), Sonic Striker (nephew), Shadow Striker (nephew), Tana Nakasa (lover), Shikamaru Striker (son), Sherera Striker (daughter)
Profile: Is prince only because of brother. Likes working on new devices. Is better at Striker spells than Striker techniques.
Likes: Elder brother, tinkering with objects.
Hates: Shadow going on a button touching spree.
Gender: Male
Fur Color(s): Yellow (primary), White, black (secondary)
Picture:

one is clothed, one is nude.

Name: Shadow Striker
Occupation: Prince, reluctant father
Age: 70
Race: hedgehog
Favorite weapon: swords
Relatives: Same as Miles and Blood, Lilith the Siren (lover)
Profile: loves to be with people. Very headstrong and arrogant. Nicknamed th ultimate life form.
Likes: being with Lilith, controlling the Knights of Mobius
Hates: the fact that he acts before thinking, which has landed him into a lot of trouble sometimes, but nailed him with Lilith (or Lily, as he calls her)
Gender: Male
Fur Color(s): Black (primary), red (secondary)
Picture:

Shadow is not wearing his cape here.

Name: Sonic Striker
Occupation: Prince
Age: 27
Race: Hedgehog
Favorite weapon: none
Relatives: same as other strikers, no lover.
Profile: Split personalities. One's a coward, one's brave and ruthless and efficient.
Likes: Uncle blood
Hates: Spiders (all of them)
Gender: Male
Fur Color(s): Blue
Picture:

Sonic is not wearing his cape.

Name: Methanos
Occupation: Ninja Corp leader
Age: unknown
Race: Methanos does not have a race, but he prefers Shadow's form
Favorite weapon: ninja tools
Relatives: Mephiles the dark (brother), Biname Queen (lover)
Profile: Good fighter. Skilled at spying. Loves being male more than female.
Likes: Biname, women
Hates: Mephiles
Gender: none, but prefers male forms (age 20-50)
Fur Color(s): crimson (primary), dark teal (secondary)
Picture:

Methanos doesn't wear shoes (or socks)