Now, if you're using paint-grade trim, you're probably thinking ... you'll need to make accurate angled cuts to fit two baseboard sections on an outside corner. Likewise, you may just not ...

For short lengths of trim (under 4 feet, say), particularly baseboard, use something ... mark the length of the wall from the inside corner to the outside, or hold it in place spanning two outside ...

The outside ends of the first and third pieces will stay at a 90-degree angle (this is where the long lengths of baseboard will meet the corner). You will use 22.5-degree angles for the miter cuts ...