One difference between a sin offering and a guilt offering was the compensation.
For a sin offering, Leviticus 4:
27 “If anyone of the common people sins unintentionally in doing any one of the things that by the LORD’s commandments ought not to be done, and realizes his guilt, 28 or the sin which he has committed is made known to him, he shall bring for his offering a goat, a female without blemish, for his sin which he has committed. 29 And he shall lay his hand on the head of the sin offering and kill the sin offering in the place of burnt offering. 30 And the priest shall take some of its blood with his finger and put it on the horns of the altar of burnt offering and pour out all the rest of its blood at the base of the altar. 31 And all its fat he shall remove, as the fat is removed from the peace offerings, and the priest shall burn it on the altar for a pleasing aroma to the LORD. And the priest shall make atonement for him, and he shall be forgiven.
Leviticus 5:
1 “If anyone sins in that he hears a public adjuration to testify, and though he is a witness, whether he has seen or come to know the matter, yet does not speak, he shall bear his iniquity; 2 or if anyone touches an unclean thing, whether a carcass of an unclean wild animal or a carcass of unclean livestock or a carcass of unclean swarming things, and it is hidden from him and he has become unclean, and he realizes his guilt; 3 or if he touches human uncleanness, of whatever sort the uncleanness may be with which one becomes unclean, and it is hidden from him, when he comes to know it, and realizes his guilt; 4 or if anyone utters with his lips a rash oath to do evil or to do good, any sort of rash oath that people swear, and it is hidden from him, when he comes to know it, and he realizes his guilt in any of these; 5 when he realizes his guilt in any of these and confesses the sin he has committed, 6he shall bring to the LORD as his compensation for the sin that he has committed, a female from the flock, a lamb or a goat, for a sin offering. And the priest shall make atonement for him for his sin.
For a guilt offering, Leviticus 5:
14 The LORD spoke to Moses, saying, 15“If anyone commits a breach of faith and sins unintentionally in any of the holy things of the LORD, he shall bring to the LORD as his compensation, a ram without blemish out of the flock, valued in silver shekels, according to the shekel of the sanctuary, for a guilt offering. 16 He shall also make restitution for what he has done amiss in the holy thing and shall add a fifth to it and give it to the priest. And the priest shall make atonement for him with the ram of the guilt offering, and he shall be forgiven.
There was a calculated compensation.
For the more intentional sins, Leviticus 6:
1 The LORD spoke to Moses, saying, 2 “If anyone sins and commits a breach of faith against the LORD by deceiving his neighbor in a matter of deposit or security, or through robbery, or if he has oppressed his neighbor 3 or has found something lost and lied about it, swearing falsely—in any of all the things that people do and sin thereby— 4 if he has sinned and has realized his guilt and will restore what he took by robbery or what he got by oppression or the deposit that was committed to him or the lost thing that he found 5 or anything about which he has sworn falsely, he shall restore it in full and shall add a fifth to it, and give it to him to whom it belongs on the day he realizes his guilt.
When you wrongly deprived of another his rights or property:
Step 1: Compensate to the person you had wronged.
Step 2: Compensate to the LORD
6 And he shall bring to the priest as his compensation to the LORD a ram without blemish out of the flock, or its equivalent, for a guilt offering. 7 And the priest shall make atonement for him before the LORD, and he shall be forgiven for any of the things that one may do and thereby become guilty.”
When a leper was cleansed, he had to offer a guilt offering (Lev 14).
Leviticus 19:
20 “If a man lies sexually with a woman who is a slave, assigned to another man and not yet ransomed or given her freedom, a distinction shall be made. They shall not be put to death, because she was not free; 21 but he shall bring his compensation to the LORD, to the entrance of the tent of meeting, a ram for a guilt offering. 22 And the priest shall make atonement for him with the ram of the guilt offering before the LORD for his sin that he has committed, and he shall be forgiven for the sin that he has committed.
When a Nazirite broke his vow, he had to offer a guilt offering (Num 6).
The Philistines returned the ark to the Israelites with a guilt offering. 1 Samuel 6:
4 The Philistines asked, “What guilt offering should we send to him?” They replied, “Five gold tumors and five gold rats, according to the number of the Philistine rulers, because the same plague has struck both you and your rulers.
Some of the exiles who returned to the promised land had foreign wives. Ezra 10:
19 They pledged themselves to put away their wives, and their guilt offering was a ram of the flock for their guilt.
For the more intentional sins, he had to offer a guilt offering.
When you wrongly deprived another citizen of his rights and property, you had to compensate him by calculating the actual amount/value plus 20%.
Outside of these civil cases, the demarcation line between sin offering and guilt offering was not so sharp. Comparatively speaking, for the more intentional sins, he had to offer a guilt offering.
