The first thing I would suggest is to leave Jita or any busy hub. This is because Horde is war-decced and you will be a target once you join, and lots of people would like to kill you in hi-sec.
You now have two options. If you have never used the ability to set your medical clone remotely (it can be done only once a year) go to Perimeter and locate the Horde citadel at Planet V. I’d recommend making a jump clone there in case you want to take part in future hi-sec fleets. Otherwise, once in the citadel you can join (press accept) and you will get an email from Kalbuir Skirate giving you lots of information on how to join and set up services. You will be guided on how to set your medical clone to our staging Keepstar in O-VWPB (the BEANSTAR). You can then self destruct and appear in the Keepstar, and then set up your Discord, Mumble etc. Contact a member of the NBI to get your free starter pack (lots of skill books, ships etc) and read the forums for your recommended skill plans.
If you have already used the ability to remote clone, you’ll have to fly to the Beanstar. In this case, before pressing Accept, I’d recommend flying to Oijanen or nearby and docking up. Click Accept and follow the guide, especially setting up your Overview correctly and joining the Bean Intel channel. You will want to have brought the fastest and most agile ship you can fly (like a travel interceptor) but keep it cheap - you might get popped on the next stage. If you are in comms, let colleagues know you are a new player and they may well come and escort you.
Check there are no (or not too many reds) on you overview. Set your destination to BWF-ZZ ( the next system, first null-sec from Oijanen. Dash for the stargate (or use use one of the bookmarked pings you will see). The gate is sometimes camped, but we clear it pretty often too. Once in BWF, you will see a Keepstar for refuge if necessary, lots of greens and blues. While still cloaked, right click in space and you will see a Jump Bridge listed. Warp to this and then right click the jump bridge on your overview to jump straight to O-V. Warp to the Beanstar and follow the instructions as before.
I hope that makes sense. If you get caught, or frustrated, just talk to one of your colleagues (the NBI are specifcally people set up to help new players) and we’ll get you there somehow