When you're getting ready to caulk, you'll have to cut the tip off of the caulk tube. If you cut the tip so that the opening is too large, your caulk job will end up looking messy. Cut the tube's tip so that the opening is about 1/8 of an inch in diameter. Cut the tip to create a a straight or blunt edge on the tube's tip and start out using the tube that way, then cut the tube tip on an angle if you think that will work better for you after using the tube for a while.
Controlling Speed of Application
To get a good bead of caulk running down the edge of your bathtub, speed is important. Be sure to apply an even amount of pressure on the tube. If you move the tube too slowly along the joint, or the area you are filling with caulk, you will have to clean up the excess caulk.
Smoothing Out the Caulk
Just after you caulk an area, smooth it out. You can use a special tool made for this, but it's just as easy to use your fingertip. Smoothing the caulk will make it look more professional and will make sure the caulk is adhering to both the bathtub and the wall. If you're using latex caulk, simply wet your finger and run it evenly across the area. When using silicone caulk, wear a latex or vinyl glove and dip your finger in denatured alcohol.
Using Tape as a Guide
For beginning caulkers, tape is a good idea, because it helps make sure the bead of caulk remains straight and in the spot where you want it, and not on the wall or the bathtub. Apply painter's tape along both sides of the joint where you will be caulking. Then run the caulk gun between the two strips of tape. Remove the tape and smooth the caulk.