We can be here all day tommorrow, the next day, and the next day, and still will not be able to finish the answer to that first question. So I'll just give a quick list for the first question:
Why do I love Jesus? Because he is King of Kings, Lord of Lords. Because despite all of my problems, he still loves me and wants what is best for me. Because in the midst of my mess, he chastizes me, so that I can become more like him. Because he is the son of God. Because his blood redeemed us from our sins. Because of this blood, if he didn't do anything else for me from this point, he has done enough to receive all glory, honor, and praise. Because he is Jehovah Jireh.
How do you love Jesus? Well, the Word says in John 14:23, if you love him, you will keep his words, and he will abide in you (referring to the Holy Spirit). So that is what we all strive to do, because even when we mess the Holy Spirit is what keeps us and even convicts us of what we need to do. Besides reading the Word, we need to spend time in prayer, especially in intercession for others. I know personally I read more than I pray, so I ask the HS to guide me and strongly convict me so that I will spend more time on my face before God. Reading and prayer is key, and when you allow the HS to lead you, everything else (such as witnessing, fellowshipping, etc.) falls into place.