I think a big preempting mistake beginners make is preempting 4H or 4S with an opening bid in 1st or 2nd position. I completely agree with destiny in #8.

 

Modern players seem to preempt a little lighter lately, although I can't disagree with Irdoz.

 

I don't worry about strength of suit as much as Irdoz, because I feel preempts are so effective. The occassional disaster is worth many good results.

 

Here are the rules I tend to use:

 

MP:

Weak 2:

1st position: Any 6 carder, 4-10 HCP. Don't care about voids or 4 card majors.

2nd position: Any 6 carder, 4-10 HCP. No 4 card major.

3rd position: Any 6 carder or good 5 carder, 4-10 HCP. Don't care.

4th position: Good 6-carder, close to opening bid.

 

3-level:

1st position: Any 7-carder, less than 10HCP. Don't care about 4-card major.

2nd position: Any 7-carder, less than 10HCP. No 4-card major.

3rd position: Any 6 or 7 carder, less than 10 hcp.

 

4-level: 8-carder with same rules as 3-level.

 

IMP:

Weak 2:

NV: Same as MP

Vul: Good 6-carder only (2 of top 3 honors)

 

3-level:

NV: Same as MP

Vul: 7-carder with 2 of top 4 honors.

 

4-level:

NV: Same as MP

Vul: 8-carder with 2 of top 4