1. Right angled line (three sides)
Right angle line of signal effect is mainly reflected in three aspects: one is the corner can be equivalent to the capacitive load of the transmission line, slow rise time; two is the impedance discontinuities will cause signal reflection; three is the angle from the tip of EMI, to the RF design field above 10GHz, these small angle may be the key problem of the high-speed object.

2, differential lines (equal length, equidistant and reference plane)
What is the differential signal? Popularly speaking, the driver sends two equivalent and inverting signals, and the receiver determines the logical state "0" or "1" by comparing the difference between the two voltages". The pair of differential signals that carry differential lines is called differential routing. The most obvious advantages of differential signals are in the following three aspects compared with the ordinary single ended signal routing:
1, strong anti-interference ability, because of poor coupling between two points line is very good, when the external noise, almost at the same time being coupled to the two line, and the receiver only cares about the two signal difference, so the common mode noise outside can be completely offset.
2, can effectively suppress EMI, the same reason, because two signals polarity opposite, they external radiation of electromagnetic field can cancel each other, the coupling is more close, the less electromagnetic energy to the outside.
3 timing, accurate positioning, due to poor signal switch changes is located in the two intersection signal, rather than relying on a single ended signal level two threshold voltage, thus by the process, the influence of temperature is small, can reduce the error of the timing circuit, but also more suitable for low amplitude signals. The current popular LVDS (low, voltage, differential, signaling) refers to this small amplitude differential signaling technique.

3, snake line (adjust delay)
Snake line is one of the frequently used routing modes in Layout. The main purpose is to adjust the delay and meet the system timing design requirements. The two parameter is the key of parallel coupling length (Lp) and coupling distance (S), obviously, the signal transmission in the snake to go online, the coupling between line segments parallel to each other, a differential form, the smaller S, larger Lp, while the coupling degree is greater. The transmission delay may be reduced, and the quality of the signal will be greatly reduced due to crosstalk. The mechanism can be used to analyze common mode and differential mode crosstalk. Here are some suggestions for the Layout engineer to deal with snake lines:
1, as far as possible to increase parallel distance (S), at least greater than 3H, H refers to the signal from the line to the reference plane distance. That is popular around the bend line, as long as S is large enough, you can almost completely avoid the mutual coupling effect.
2, to reduce the coupling length Lp, when two times the Lp delay close to or exceed the signal rise time, the resulting crosstalk will be saturated.
3, the delay of signal transmission caused by serpentine line of strip line (Strip-Line) or embedded Micro-strip (Embedded) is less than that of microstrip line (Micro-strip). In theory, stripline does not affect transmission rates due to differential mode crosstalk.
4, high-speed and timing requirements of the more stringent signal line, as far as possible not to snake line, especially in a small range of winding lines.
5, you can often use any angle snake line, can effectively reduce the mutual coupling.
6 、 in high-speed PCB design, snake line does not have the ability of filtering or anti-interference, it can only reduce the quality of signal, so it is only used for time series matching without other purpose.
7, sometimes spiral winding can be considered, and the simulation shows that the effect is better than the normal serpentine line.