Warfare & Tactics

1. Scan down something (or better multiple somethings) outside the range of the planets and then create your BMs.

2. Safes aren't "Needed" for any ships, but are generally advisable for ALL ships (not having them just means you are going to die a lot).

3. Yes, though generally you don't want them right on the undock due to that being where most campers will setup to be in range of.

4. Nah, but make pounces.

5. When warping to a gate.

I build and sell bookmarks for a living. So what you see below is my perspective on these matters. No doubt there will be something incorrect below, altho I will try and prevent that from happening, and no doubt a number of people will wish to disagree with stuff I say, so it’s up to you to filter this and take or leave whatever you wish 

1. There are a variety of methods of making safespots. Not-so-very-long-ago there were even more but the then deep-safe-spot methods got nerfed out of game. Nowadays you are basically limited to ‘celestials, sigs, and anoms’ for the manufacture of safespots. I build an awful lot of safespots for my many for-sale bookmark packages and for general purposes I mostly use planets and gates for making safespots. When the system geometry requires or the circumstances allow, sigs and anoms … especially wormholes, allow for better quality safespot manufacture. Incursion sites, when an incursion is visiting the area, make for superb safespot manufacture.
The basic approach is to try an build your safespot somewhat out-of-the-way and not directly between any two celestials. That way you reduce the likelihood of an uncloaked ship sitting at the safespot being noticed on DS and make it unlikely that anyone warping between locations will see an uncloaked ship flash by on overview during their warp. Just how remote and how far off-the-beaten-track your safespots are will depend on needs and your own preferences.
In some systems it is now impossible to build a new safespot that is out-of-DS-range from all celestials and sites, but that is still eminently do-able in many systems. Some old-timers, holding nerfed deep-safe bookmarks, can still build such safespots in systems where it is not possible to do so afresh.

2. Safespots are not always necessary for covops ships, but they are still useful for covops. For example, when I am scouting a region in a covops, I usually build a decent safespot when I want to uncloak and voucher-copy a bundle of bookmarks to hand over to another character … because you cannot do that particular bookmark manipulation while cloaked.
Safepots have many uses, but their main use is implied by their name … they provide players and their ships with a safe location, even if it can only be relied upon to be partially safe and for a short period of time. During a pitched battle in a hostile system with dozens of combat probes aloft it can provide a much-welcome reprieve to have a reliable safespot to warp to, even if you are only there for a few seconds and immediately warp to another location … usually building further temporary safespots during those warps.

3. An instadock is simply a location that is within docking range of a station or outpost (usually showing the station at 0km on overview) and yet is far enough away from the station/outpost graphic to make bouncing exceedingly unlikely. These are built with a similar approach to cyno-spots, working with reference to both the model (image) of the station and the overview.
An Instawarp undock bookmark, different beastie to what you’ve asked about, is used to allow ships to instantly warp away from the station/outpost upon undocking. I build all my instawarps at a distance likely to be offgrid even after the most likely gridfu activity, and in the middle line of the undock arc. When a ship undocks they move naturally away from the station/outpost in a semi-random direction within cone centred on that middle line. This means that there will be an align-time element for anyone undocking and warping to a bookmark. To keep that align-time to a minimum, on average, you try to build your undock instawarp bookmarks as close to the centre-line of that cone as you can.

4. No. In the good-old-bad-old days you could not warp to a gate at zero km, so people built and sold bookmarks behind the gates so you could warp to the bookmark at-range and land at zero on the gate. Nowadays you can warp to gates at zero km from anywhere in a system (notwithstanding bubbles messing with that plan).
There are situations where bookmarked locations very close to a gate are used but those are specialty applications.

5. Smartbombers use a variety of methods and can operate on either side of a gate. When there is a risk of smartbomber activity I try to use perch bookmarks near an outgate to get visual confirmation of the status, and map tools (along with other intel tools) to get an indication of the situation in the system I am planning to jump into.