A sloper and/or block is a flat pattern with ease built into it. This means that the pattern fits closely, but has the ease you like. Starting with a dot, and by creating measured horizontal and vertical lines, you create this pattern. As a bonus, there are basic instructions at the end for the skirt block/sloper which can be added to the bodice to make a dress. For the Sleeve Block/Sloper, check that out here. With the bodice, skirt and sleeve slopers, you can create your own basic model pattern that will fit you.
The basic process is many steps, however each step is copiously documented and if you take this step by step, it's not that hard. The one document to download has the links to all the videos and other download material you need. I highly recommend you do the math on the steps before you start drafting. What may seem insurmountable, becomes easy and well-described steps to making your own well- fitted garment.