these are some 12 bar blues riffs i made up. im reli bored so im going to tab em. 

1) this is easy to play and shouldnt cause a problem for any of you.

E|--------------|-------------|-------------|--------------|
B|--------------|-------------|-------------|--------------|
G|--------------|----7h9-9-9-9|----5h7-7-7-7|--------------|
D|-----5h7-7-7-7|7h9-----9-9-9|5h7-----7-7-7|-----5h7-7-7-7|
A|-5h7-----7-7-7|--------7-7-7|--------5-5-5|-5h7-----7-7-7|
E|---------5-5-5|-------------|-------------|---------5-5-5|
  ---X3--------/-----X3-----/-----X3-----/------X3-----/

2nd also very easy.

use these as your 12 bars G G G G Dm Dm Cm Cm G G Dm Cm

use this strumming patturn this counts for all of the chords 
used not just the G wich i have used as an example
   G
E|-3-3-3-x-x-33-3-3
B|-3-3-3-x-x-33-3-3
G|-4-4-4-x-x-44-3-4
D|-5-5-5-x-x-55-3-5
A|-5-5-5-x-x-55-3-5
E|-3-3-3-x-x-33-3-3