2 Corinthians 9:7
Each one must give as he has decided in his heart, not reluctantly or under compulsion, for God loves a cheerful giver.
Observation: God loves a cheerful giver.
Problem: Don't like to give?
Solution: Don't be cheerful.
God likes only cheerful givers. He would never ask you to do something you didn't want to do, right?
God commands you to do all sorts of things you would not naturally desire to do. And thank God for it. His ways are not our ways and His thoughgts not our thoughts. But God does not simply tell you to do something without providing you a new heart by which to obey His commands. He gives what He commands. God may command you to give, but He delights in one who does so cheerfully.
If you don't give, it is likely because you simply don't want to. You shouldn't have to be coerced into giving by worldly guilt, or worse guilt in the variety of Law-Gospel-Law (specifically the 5th paragraph beginning with "but something..." although the whole article is worth your time and meditation). If you don't want to give, don't. Maybe you don't have a new heart. Maybe you're not regenerate or reborn.
Maybe? It is a possibility, isn't it?
Or you are a reborn, regenerated Christian who is struggling with the old man who still loves storing up in bigger barns and has yet fully to be broken into submission to Christ's call to generosity. But if you are a Christian, then wrestle with the old man - for Christ's and your own sake! Don't just let the old man lead you in this area. Don't rest in the assumptive, seductive draw of "someday."
Someday I will give more.
Someday I will do then what I know I am commanded to do now.
As long as "someday" remains an IOU to excuse present rebellion, "someday" will never come. You don't want it to.
Quality time is bred from quantity time. You cannot plan quality time. In the same way, perhaps cheerful giving is bred from thanfulness for what one has. You cannot plan on being cheerful about something difficult and pull it off honestly anymore than you can orchestrate quality time next Tuesday at 2 pm. It happens, unexpectedly, as a result of diligence and duty. Not merely plodding along in drudgery per se, but obediently performing the task that lay at hand if for no other reason than (1) "it lay at hand" and (2) you can do it.
Ask that God would give you a new heart to enjoy giving, seek opportunities to give, and be cheerful throughout the whole ordeal.
Decide in your heart what you will give.
If you have never done this, do this!
There is no mystery as to what Scripture is commanding you to do here.
The seeds of generosity are planted by gratitude and grow up to produce fruit in keeping with grace. Grace begets grace. It initiates the process and produces in its object that which it bestowed at the onset.
God loves when people love Him and from that compulsion give.