Phill, do the job properly or not at all.
The adhesive used in electrical tape will sooner or later fail, and rim tape needs to be the specific width for your rim. Electrical tape won't be the correct width, and I'd suggest choosing where you take advice from wisely.
Just two examples of rim tape for you. Each link only shown as an example, and not seller recommendation.
Firstly Caffe Latex, which I have yet to use, but reports are seemingly very good.
http://www.chainreactioncycles.com/effetto-caffelatex-tubeless-rim-tape/rp-prod150141?gs=1&gclid=CMqE5rSU6s8CFbUV0wodSs8MOA&gclsrc=aw.ds
Second Stans. I have used this with great success on the last three bikes.
http://www.chainreactioncycles.com/stans-no-tubes-rim-tape/rp-prod38829
In respect of sealant. I didn't have any luck with Stans, and found it to ball up into a rubberiesd mess, very quickly. Others have had great success with it though, and if it was crap then the company would have gone out of business a very long time ago. They haven't and I can only assume that I was unlucky.
My prefered choice is Effetto Caffelatex, which I have yet to find fault with.
http://www.chainreactioncycles.com/s?q=effetto+caffelatex+tubeless+fluid&cat=product
Fitting of a tubeless kit has been covered in the other thread so there is no need to detail that again.
If you are still unsure, I'd recommend speaking to the cycle shop that supplied the bike to you. They have financially done very well out of you over the last few months, and I'm sure that they would be more than happy to advise or fit the kit for you. The kit is easy to fit your self, but if in doubt, then get them to do it for you.
I appreciate that going tubeless is an expensive undertaking when done correctly and not just a bodge job, but the expense is easily repayed time and time again. There is never a good time to get a flat tyre, and whilst a tubeless set up won't offer 100% protection, it is pretty close.
If you do go tubeless, still don't neglect taking along some means of puncture repair, be that a tube or tubeless repair kit.