This is a guide to help you improve your roleplaying.
Now, your post can be broken down into three main parts.
Description
Action
Dialogue
Thoughts
Keep that in mind when you're posting.
Description is the best one to start with.
An easy way to describe things is think of your senses. What you see, what you hear, what you smell, what you taste, what you feel. Not all of these are appropriate all the time, but you can use at least two of them in each post. Sight can be used in every post. Describing places, people, objects, anything. What you hear can also be used. Are there people talking? Are there animals around? Are there scratching quills? Or is it dead silent? Description can be used in the first post/your first post in the topic, it doesn't have to be used in every post as the setting/people don't change much between posts.
Try to include what your character likes or dislikes about the description.
Example:
Jemma looked around the Great Hall, amazed. It was massive! She had never seen anywhere so big in her entire life. There were people everywhere talking constantly.
Action is either the second or third one.
It's often considered the easiest one. Simply, what is your character doing? Standing, sitting, lying down, leaning, what position are they in? Or are they moving? Entering or exiting a place? Turning to face or avoid someone? Heading towards somewhere? The possibilities are endless. You can then add why they are doing it. Do they like or hate someone? Are they tired so going to bed? Use your imagination.
Example:
Jemma walked over to the Hufflepuff table and sat down. She picked up some toast from the plate as she was starving. She started spreading butter on it.
Dialogue is normally second or third.
This is either a response to what other characters have said or starting a conversation with them. If you're starting a conversation, you normally say 'hello' and introduce yourself if you don't know the person. Or if you've forgotten their name. Try not to use 'said' after every bit of speech. There are many other words you can use. Answered, replied, responded, introduced, implied, emphasized, began, started, told, yelled, screamed, begged, joked. You can also add an adjective afterwards if you want to be really fancy, like 'started nervously' or 'yelled constantly'. Dialogue should always be in speech marks, but some people like to bold or colour it too. I would suggest bolding, as colouring is sometimes hard to read, but it's up to you.
Example:
"Hi, I'm Jemma." Jemma introduced herself to her fellow Hufflepuffs. "I'm a first year." she added nervously.
Thoughts/Feelings are normally throughout the post, mixed in
They are simply what your character thinks about things. The easiest way to do this is ask your character why they did something, why they said something, why they like or dislike something. Why? Feelings are similar, but this time, ask what they felt about something. It's just opinions. Some people like to put thoughts in italics, it's up to you.
Example:
Jemma was really nervous because she had never been surrounded by so many people. What if they don't like me? she worried. She felt uncomfortable with so many people in the room.
Put it all together:
Jemma looked around the Great Hall, amazed. It was massive! She had never seen anywhere so big in her entire life. There were people everywhere talking constantly. Jemma walked over to the Hufflepuff table and sat down. She picked up some toast from the plate as she was starving. She started spreading butter on it. "Hi, I'm Jemma." Jemma introduced herself to her fellow Hufflepuffs. "I'm a first year." she added nervously. Jemma was really nervous because she had never been surrounded by so many people. What if they don't like me? she worried. She felt uncomfortable with so many people in the room.
Over a hundred words. It's not that difficult, is it?
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