Going DIY can offer the Christmas enthusiast cost savings, potential customisation and the satisfaction that you made it yourself!
Try to buy good quality tools wherever you can. You don't have to go top of the range, but really cheap and nasty tools will invariably perform poorly, break prematurely and cost you more in the long run.
If you plan to assemble circuit boards with through hole components, a good pair of flush cutters is essential. The pair pictured below-left are ideal for trimming off component legs.
For heavier duty jobs, such as cutting power cables, a larger pair of side cutters (pictured below-right) are the right tool for the job. They are not as precise as the flush cutters, but won't be damaged as easily either.
Like cutters, you'll need more than one set of pliers. A small, precise set (below-left) for fine work such as bending component legs, as well as larger ones for heavier duty jobs will serve you well. For the larger ones, a set of combination pliers (pictured blow-right) can serve double duty as heavy wire cutters.
You'll need a selection of screwdrivers in DIY. The most economical way to buy the common sizes is in a set. You should find reasonably priced sets (under $30) at your hardware or tool store.
Flat blade screwdrivers are straightforward enough, but be careful with cross type. Most commonly called phillips head, they can sometimes actually be a pozidrive head. A phillips head driver has just 4 points, whereas a pozidrive has an extra smaller point between each. Using the wrong type of driver will damage both the screw head and the screwdriver!
For SMD work, a couple of pairs of tweezers is also handy. One pair of fine point and one pair of self closing type will help hold small parts in place.
The crimper picture below is designed to crimp 4, 6 and 8 way modular connectors. It has a simple ratchet action for reliable crimping and a cable cutter/stripper.
If you're going to crimp a lot of QC terminals, a good quality crimper (below-left) will last you a lifetime. The cheap ones (below-right) are usually flimsy and seldom produce a reliable connection.
===Irons / Stations===
There are a myriad of soldering irons and stations on the market. For electronics work, something in the 20W to 50W range is ideal. For occasional work, a 240V temperature controlled 20W iron (below-left) may be all you can justify. A higher powered soldering station (below-right) with low voltage iron will work better and have a larger range of tips available.
For removing components from circuit boards, you can use a solder sucker or solder wick (braid). Solder suckers use a one-shot vacuum action to suck up molten solder. Solder wick will usually remove more solder, but is an expensive consumable.
With solder wick, don't stick your fingers all over the braid. The oil in your skin kills the chemical in the braid and can render it almost useless.
One thing the DIY'er is bound to use is heatshrink tubing. That means you'll need a heat gun! The heat guns sold specifically for heatshrink are usually just paint stripper guns with a fancy label and a higher price. They may come with different add-on nozzles of course, but the paint stripper ones work fine. Just be sure to heat all around the tube (not just from one side) and not dwell on one spot for too long.
As for what size heatshrink to buy, 3mm and 5mm are the most commonly used ones. For joining or repairing DC LED strings, 1.5mm (or 2mm) is also a really good size. You can buy it from Altronics, Jaycar or one of the many sellers on eBay or AliExpress.
A digital multimeter is an essential piece of test equipment. I recommend an auto ranging meter. This removes the uncertainty and confusion of selecting the correct range. You will still need to select Volts (AC or DC), resistance (Ohms), etc though.
One example of an inexpensive auto ranging meter is this one from Jaycar. Do not bother with the cheap nasty $20 types. Buy one with a "CAT III" marking as this indicates that it is suitable for 240Vac use.
Another type is the UNI-T UT61E. It's available on eBay for about $65 upwards.
A power supply with a variable output (or several fixed outputs) can be very handy. There are a few articles on the 'net that show how to convert a PC power supply for bench use.
For holding board, wires and plugs steady, sometimes a "helping hands" and mini vice can be useful. A pin vice in conjunction with very small drill bits is handy for clearing clogged holes in PCBs. A component leg forming tool makes bending resistor legs a snap. Lastly, if your DIY project goes horribly wrong, a sledge hammer will may give you some satisfaction!
Here's a few links to tool suppliers: