[GM] Jumping...

Can someone please help me, step by step, how I can make a character jump Right now I have:
Check whether in the air.
If a position is collision free x:0 y:0
Set the gravity to 50 in direction down
Else
Set the gravity to 0 in direction 0
Limit the vertical speed.
If vspeed is larger than 12 (variable)
Set the vertical speed to 12

I am sure this sounds retarted, but I just can't get it, as right now what happens is He'll jump, but won't come back down x_x. Please help.

Also, I read the platforming tutorial, I was so confused >_<

Thanks

Well 1st of all, you need to check if there's a collision below your character, not on the character, So change the  "If a position is collision free x:0 y:0" to "If a position is collision free x:0 y:1" Also you've set the gravity really high compared to your max vertical speed. Try setting the gravity to 2 or 2.5. Thats may help. If all this doesn't work, I'll be here to help if you need it.

I'm having a problem with the character landing, it lands about 4-8 pixels above the ground, but if I move the character will land on the "ground". Here is how I have my events/actions set:

                                        (Character)Mario_Right_0(stationary Mario pic)

Create: Set Grav to 2 at 270 Degrees(How come there is no degree key on a keyboard? sorry, back to the point)
Collision with L_Edge_Grass_01: Set Grav to 0 at 270 Degrees
Collision with C_Grass_01: Set Grav to 0 at 270 Degrees
Collision with R_Edge_Grass_01: Set Grav to 0 at 270 Degrees
Press(Space): Jump to given position X,0 Y,-48
                     : If a position is collision free X,0 Y,1
                     : Set Grav to 2 at 270 Degrees
Press(Left): If a position is collision free X,0 Y,1
                 : Set Grav to 2 at 270 Degrees
                 : Change Sprite to Mario_Left_1(animated gif of mario moving left)
                 : Start moving in a direction(Left)
Press(Right): If a position is collision free X,0 Y,1
                   : Set Grav to 2 at 270 Degrees
                   : Change Sprite to Mario_Right_1(animated gif of mario moving right)
                   : Start moving in a direction(Right)
Release(Left): If a position is collision free X,0 Y,1
                   : Set Grav to 2 at 270 Degrees
                   : Change Sprite to Mario_Left_0(Stationary pic facing left)
                   : Start moving in a direction(Stop)
Release(Right): If a position is collision free X,0 Y,1
                   : Set Grav to 2 at 270 Degrees
                   : Change Sprite to Mario_Right_0(Stationary right facing pic)
                   : Start moving in a direction(Stop)


Well that sums up what I have so far. It's just not working quite like I would like and I didn't want to make a seperate topic since this already dealt some with jumping.

first, to Rathalos888: you also need to set you gravity 0f 270 to 0

second to LostNSpace: why not use (no Key) in the events under keyboard(not pressed or released.