Several others have already answered your question, but whatever...
Here is my attempt:
CREATING A CHARACTER FOR YOUR GAME
Follow these instructions step-by-step and you will be fine. Ask if you have any trouble or if you are not sure about what to do at a point.
1. Draw your character in a program like MS Paint (you said you already did that). You need to draw him in all possible poses (front view, side view, back view) and later on you also need to draw every single frame for the animations (walking, picking up something etc.) but for now let's keep with only one image: the front view. So you draw him facing towards the viewer.
2. Save your image (File->Save As) into some location on your hard drive. Ideally you would want to create a folder for all images in your game (for example "C:/My AGS Game/", then you could save him as "C:/My AGS Game/Character.bmp"). Make sure to save the image as .BMP and not .JPG or something else.
3. Now it's time to switch to AGS, so start the editor and load up your game or start a new one.
4. Select "Sprite Manager" on the right side of the editor.
5. Now right-click somewhere into the big white area to your right and select "Import new sprite..." from the menu.
6. A little window will pop up, click on "Import from file..."!
7. Now you'll see a standard windows dialogue window. Select your character image from where you saved it before (in my example it was "C:/My AGS Game/Character.bmp") and double-click on it.
8. Now you are taken back to the little window from Step 6. You should see your image in this window by now. Click on "Grab entire image"...
9. This should then add the image to your game. You should now see it as entry in the big white area to your right.
10. Next click on "Views" in the left menu (one entry after "Sprite Manager") and click on "New View" at the bottom of the screen.
11. This should add a new entry to the list on the middle white area called something like "VIEWXX" where the X's are replaced by some numbers. Make sure that this new entry is highlighted and thus selected by clicking on it.
12. Now it should say "Loop 0 (down)" to the right. Click on the text that says "New frame" and then double-click on the blue cup image that gets inserted.
13. The next screen looks familiar: We're back in the "Sprite Manager". Now double click on your imported image.
14. This should take you back to the "Views" page - now your image should be the first image under "Loop 0 (Down)".
15. Allright, the view is set up, now we come to the final step: the character. Click on "Characters" on the left side (one entry after "Views").
16. Then click on "New Character" at the bottom of the screen. Highlight the new entry in the list (like you did with the view before) and click on the button that says "Normal view: 0".
17. A little dialogue should appear where you can insert the number of the view that you created before. If you don't remember it, than click cancel and switch to the views screen, remember the number and repeat the above steps.
18. Now you're done. You'r character is there. You should now adjust some settings for it, that you can find in the "character" view (like "player character" or its position etc.)
Phew, this was quite a detailed explanation, but still - in a few days this will all go in less than 2 mins, I assure you.
Here is my attempt:
CREATING A CHARACTER FOR YOUR GAME
Follow these instructions step-by-step and you will be fine. Ask if you have any trouble or if you are not sure about what to do at a point.
1. Draw your character in a program like MS Paint (you said you already did that). You need to draw him in all possible poses (front view, side view, back view) and later on you also need to draw every single frame for the animations (walking, picking up something etc.) but for now let's keep with only one image: the front view. So you draw him facing towards the viewer.
2. Save your image (File->Save As) into some location on your hard drive. Ideally you would want to create a folder for all images in your game (for example "C:/My AGS Game/", then you could save him as "C:/My AGS Game/Character.bmp"). Make sure to save the image as .BMP and not .JPG or something else.
3. Now it's time to switch to AGS, so start the editor and load up your game or start a new one.
4. Select "Sprite Manager" on the right side of the editor.
5. Now right-click somewhere into the big white area to your right and select "Import new sprite..." from the menu.
6. A little window will pop up, click on "Import from file..."!
7. Now you'll see a standard windows dialogue window. Select your character image from where you saved it before (in my example it was "C:/My AGS Game/Character.bmp") and double-click on it.
8. Now you are taken back to the little window from Step 6. You should see your image in this window by now. Click on "Grab entire image"...
9. This should then add the image to your game. You should now see it as entry in the big white area to your right.
10. Next click on "Views" in the left menu (one entry after "Sprite Manager") and click on "New View" at the bottom of the screen.
11. This should add a new entry to the list on the middle white area called something like "VIEWXX" where the X's are replaced by some numbers. Make sure that this new entry is highlighted and thus selected by clicking on it.
12. Now it should say "Loop 0 (down)" to the right. Click on the text that says "New frame" and then double-click on the blue cup image that gets inserted.
13. The next screen looks familiar: We're back in the "Sprite Manager". Now double click on your imported image.
14. This should take you back to the "Views" page - now your image should be the first image under "Loop 0 (Down)".
15. Allright, the view is set up, now we come to the final step: the character. Click on "Characters" on the left side (one entry after "Views").
16. Then click on "New Character" at the bottom of the screen. Highlight the new entry in the list (like you did with the view before) and click on the button that says "Normal view: 0".
17. A little dialogue should appear where you can insert the number of the view that you created before. If you don't remember it, than click cancel and switch to the views screen, remember the number and repeat the above steps.
18. Now you're done. You'r character is there. You should now adjust some settings for it, that you can find in the "character" view (like "player character" or its position etc.)
Phew, this was quite a detailed explanation, but still - in a few days this will all go in less than 2 mins, I assure you.