Notice those lines that are covering the background ? These will help us align our image perfectly.

Now, enable the Snap To option (View > Snap To > Grids). This will make adding Anchor Points easier.

Next, we select the Pen Tool (P).

 

Choose a point on the grid, somewhere near the middle. It doesn't have to be perfectly centered, as long as you set your beginning point on top of a line. Preferably, at the section where the Vertical Line and the Horizontal Line connect. At the Crossroad, so to speak.

Click the Crossroad with the Pen Tool. You will get a tiny point.

Now, move your mouse left one Grid Section, and down Three Grid Sections. Do not drag the mouse. Click on the Crossroad at this coordinates.

Next, we move the mouse left three Grid Sections, and click the Crossroad Point there.

 

Now, starting from our current position, we move down one and a half Grid Sections and two and a half Grid Sections to the right.

 

Now, starting from the next Large Grid line below our current position, we move down two and a half Grid Sections and left one Grid Section. This brings us between two Large Grid Sections. Click it.

 

Now, starting from the nearest Grid Section on top of our current point, we move up one and three quarter Grid Sections, and right three Grid Sections. Click it. We should be on the same grid line as our first point, just about 5 sections lower.

 

No worries, we are two quarters of the way there (pun intended). The rest will be easy.

Next, we move right two and a half Grid Sections and down to the same level as the Lowest Point on our star. Make sure they line up Horizontally.

 

Now, we move left one Grid Section and up three Grid Sections. It should also line up with its Mirrored Half. Click it.

Right two and a half Grid Sections and line it up with the Mirrored Half. Click it.

 

Next, left three Grid Sections and click it.

Now, back to the starting point and click.

 

A perfect star, if all went to plan.

What do we do with it?

Go to the Toolbar and Right Click the Pen Tool. Choose the Add Anchor Point Tool.

 

Now, go to the top portion of our star. Go down two Grid Sections. Click it once on the line surrounding the star. Now, hold your mouse over the area, and click it again, this time don't let up. Drag the mouse outward one quarter of a Grid Section.

 

See it ? It created a near rounded curve. Repeat this proccess across the rest of the star. Make sure to click to add an Anchor Point, let up and the re-click to manipulate it.

Turn off your Grids - (Control + "). Now, our star is starting to look nice, yes ? Here are some of the designs I just threw together for this Tutorial. I hope you enjoyed it, and maybe even learned a thing or two. To save yourself some time, go to Edit > Define Custom Shape > Name Your Shape to turn it into a Custom Shape.