these riffs will help you warm up!!
i hope.....well enjoy  

1)
|--------------------|
|--------------------|
|:------------------:|repeat 4 times
|:---------4---2----:|
|---2-3h4----4---2---|
|--------------------|

2)
|------------------------------|
|------------------------------|
|:----------------------4-4---:| 
|:---2-2--2p4-----------4-4---:|repeat 2 times
|----2-2------4--3-3-0--2-2----|
|----0-0-----------------------|

3)
|----------------------|
|----------------------|
|:--------------------:|  play this one fast 
|:--------------------:|  and repeat 3 times
|--------3-------------|
|---0--0---4--2-2--5---|

4
|-----------------------|
|-----------------------|
|-----------------------|
|-----------------------| play this one fast like Slayer - Raining Blood main riff speed type
|-----------6---5-------|
|---0-0-5-7---7---7-4---|

All Done
...by kevin timmers