After we overcall, responders bid of a new suit at the 2 Levels is natural and constructive, but non forcing.
New suits at the 1 level are NOT forcing.
New Suits at the 3 level or higher are forcing (usually to game).

Where a new suit is non Forcing (1 and 2 level), then a JUMP in a new suit is Natural, and Forcing, and really strong. Don't be afraid making non forcing responses to one-level overcalls with quite good hands.

Jump shifts in new suits are FIT SHOWING JUMPS.
Fit Showing Jumps are usually 9 cards between 2 suits, and are geared towards winning the auction, but don't setup a force.
Jump shifts in an opponents suit are Splinters and Game Forcing, and setup a force when we are vul.

If our overcall is in a Major, We play Giorgio.
If our overcall is in a Major, 2NT is a good 4 card raise.

An exception to this rule applies when responding to an overcall at the 2 level where a simple raise would show a constructive hand. ie.
(1S) 2H (P) ???
If we overcall in a minor and the third hand bids at the 2 level, then 2NT shows a competitive raise and 3m shows a constructive raise. Ie.

If the opponents double an artificial support bid, returning to the trump suit is the weakest option. Pass is mildly encouraging.

Cuebid or Giorgio advances to an overcall don't 100% promise a fit (usually a fit)

In response to a 1-level overcall, you swap the meaning of 2C and CUE
Only on through a PASS or DOUBLE
(1any) 1suit (PASS) ??
Now:
..2C - ART: Cue Raise
……then 2D: OK overcall, not accepting INV
……and 2suit: terrible overcall
……others Game Tries+
..CUE: SHOWS CLUBS, constructive
……2suit/3C non F

2C Giorgio might be made on hands that want to force, but can't bid a suit at the 1 level.
If the 2C bidder later bids a suit, its a v strong hand, nat, might not be a fit.

(1C) 1H (P) ???

1S = Natural. 4+S, non-F but rarely passed
1NT = Nat 7-13. With a sound overcall (13+ HCP) opener cuebids.
2C = Giorgio INV+ Heart raise (OR rarely GF without support.)
2D = Natural, Constructive, non Forcing
2H = Simple raise
2NT = 4 card raise, usually balanced. System ON by opener.
2S = Natural, Forcing.
3D = Fit Showing Jump
3C = Mixed raise, 7-9 HCP and 4+H.
3H = Preemptive raise, 0-6 HCP and 4+H.
3S & 4D = Fit Showing Jumps
4C = Splinter
4H = To play (can be very wide ranging)

(1D) 1S (P) ???
1NT = natural, 7-13 HCP. With a sound overcall, (13+ HCP) opener cuebids.
2C = Giorgio Spade Raise
2H = Natural, Constructive, non-Forcing
2D = Clubs (Giorgio)
2S = Simple raise, 5-9 HCP.
2NT = 3/4 card GF spade raise.
3C/3H = Fit Showing Jump
3D = Mixed raise, 7-9 HCP and 4+S.
3S = Preemptive raise, 0-6 HCP and 4+S.
3NT = to play.
4C = Fit Showing Jump
4D = Splinter
4H = To Play

(1C) 1H (x) ???
as above:
xx = Snapdragon. Hx support with scattered values. (lead directing)

(1S) 2H (2S) ???

X = Negative (both minors)
2NT = Cue Raise (INV+)
3C/3D = Nat, Forcing.
3H = Simple Raise.
3S = GF raise.
3NT = To play.
4C/4D = Fit Showing Jump
4H = To play.

(1H) 2D (2H) ???
2S = Nat, constructive but Non Forcing
2NT = Weak Diamond raise.
3C = Nat, Forcing
3D = Constructive Diamond raise.
3H = Stopper ask (implying support) or a strong single suited spades hand.
3S/4C/4NT = Splinter.
4D = Preemptive.
4H = RCK, Diamonds.
3NT = To play

(2D) 2H (P) ???

2S = Constructive, NF
2NT = ## GF Raise.
3C = Natural, Forcing.
3D = Inv Raise, or G/F spades.
3H = Constructive.
3NT = To play.
3S/4C/4D = Splinters.
4H = To Play