Where is the Illustrator scallop tool ?? Go to the tools panel and go to the width tool and then down to the scallop tool in Illustrator and apply this to any current selected path.
You can use it to create a fancy edge around a path. You can use it to create randomize distortion / warping to your path. You can use it to give a sort of hand drawn look to your artwork. You can distort a design locally or overall. Create lots of extra points to manipulate with other features. It is applied to the path and not to the color or stroke etc of an object.
To see the options, double click the icon or just press return. Sadly, you cannot use the feature while the dialog is active (why ??). The settings are same as the others in this group such as wrinkle etc such as width, height, angle, intensity, use pressure pen, complexity and detail, brush affects tangent (in and out) etc as well show brush size.
To create very subtle modifications then set the width and height to a very low value. If you want to apply a slight effect then increase the height and width and then lower the intensity to 1% and it can be used to create a sketch like effect with the path or selected paths, and you can use it to any number of selected paths.
You can set the angle say to 45 degrees but with the random curves etc this is not such a useful setting (though people may disagree). I would suggest changing the height and width to something 1:4 or 3:1 etc and then use the angle feature. You can set the height to 400pt and the width to 20pt etc in the options and apply that with the angle setting. You can use that to create an interesting cutting effect as you apply it across the design, though the intensity will probably need to be 100%. If you set the line too thin, the design won't alter too much but it will probably generate a lot of points.
The complexity and detail entries are dangerous, if you are going to use those then I would suggest backing up your current file as I have found a lot of crashes with using large settings as well as just applying the tool a few times as it creates a lot of paths. They are useful but they need to be used with care.
Brush affects anchor, tangent etc are useful for creating variants with one moving the points and the other the tangents etc. The scallop tool can be used to create all kinds of weird and wonderful warping, I like to use it with a size bigger than the path you are applying it to.
You cannot use it with text but if you wish to, the object menu and expand. You can now apply it to the individual characters but you will not be able to edit the characters. You can use it to create some truly extreme text distortions.
You can create a gradient mesh via the object menu and then re-color it using the mesh and select all the points by using the direct selection. You can then apply the warping effect to create an interesting painter like effect with the current selected paths.
Sadly, you cannot use this in combo with the appearance panel where you can set up multiple strokes or multiple fills but you can always workaround this by duplicating the path and then apply it. Hold down the alt / option key and duplicate and then apply the effect to the top object and the unselected original will not be edited using the warping features. You can then warp the top artwork leaving the original untouched. You can also then use the blending modes as well as opacity to blend between the original and the duplicate such as use darken or multiply. Or change the colors of the original or the top object and then combine those with the warped effect and untouched original.
Duplicate the object. If you want to create a hand drawn effect, remove the fill from the top object and just use the stroke and have that selected and have the original unselected. You can then vary the weight for the strokes for each of the paths and then apply to those together or individually. You may like to set the intensity to a low value otherwise the effect maybe a little too extreme with all the lines pulled in. You can then slightly offset the stroke paths and perhaps change the colors a little for the stroke so it is not a solid black or perhaps change the opacity so it is not 100% etc. All kinds of tangled lines can then be added around the edge of your design