A sensible way to ensure that devices are not damaged is to use IC holders and to insert the devices only when construction is complete and the layout has been checked. Plastic insertion and removal tools are not expensive and are preferable to fingers for manipulating the devices. No device should be inserted while power is applied to the Circuits and obviously one should make sure that the device is inserted the right way round. Most CMOS ICs are equipped with internal protective diodes which limit voltages at the inputs to a safe level, but care is still advisable in handling them. If they have to be soldered in directly, the V DD pin should be connected before any earth connection is made.
Some beginners are anxious about the possibility of component damage during soldering operations.
It is true that some components are affected by heat, for instance, resistors change their value when heated, and extreme heat can damage Semiconductors such as diodes and transistors. The best way to avoid such damage is to acquire sound soldering technique. If the surfaces being soldered are clean, the soldering iron need only be applied to the joint for a short time, and the temperature rise in the body of the component will be too small to cause any damage. One can buy soldering stunts to clip on transistor or other leads during soldering operations, but they are really unnecessary - a pair of flat nosed pliers can be applied where one needs to avoid heat being conducted to a sensitive device.